PEPSI Exposure Time Calculator (ETC)<\/title>\r\n<script type=\"text\/javascript\" src=\"https:\/\/pepsi.aip.de\/etc\/math.min.js\"><\/script>\r\n<script type=\"text\/javascript\">\r\n function snestimate() {\r\n var fluxarr = [\r\n [239593039.763,178543473.813,124031554.257,82534178.9555,52094588.3886,30216798.7116],\r\n [224137694.103,172205034.458,126093669.89,80045933.2903,51523158.0048,30126736.1341],\r\n [228955744.058,174893335.89,123225191.932,83093894.2227,53409615.9756,31982647.2655],\r\n [203867603.322,163612745.223,121765478.951,84705239.0309,54203841.1893,34916553.3623],\r\n [193000258.246,159633040.67,120739509.738,83739958.6425,56950404.9026,37220541.4696],\r\n [196964790.184,156444685.295,119223858.616,85247685.164,60502251.1293,40693294.6208],\r\n [185401043.818,147695755.167,113467540.659,87920455.11,60709980.127,42093478.8237],\r\n [167909073.769,146713180.85,116465787.385,89571584.9871,64926699.746,43691869.1895],\r\n [167158116.581,145482676.804,114951518.904,88475523.2607,65030701.9542,46120088.6093],\r\n [157760706.291,137836455.92,113379915.298,91641365.1536,68924700.2428,48698033.483],\r\n [143607150.179,127875584.892,112520771.519,93223216.4379,70387887.7272,50546712.6645],\r\n [112483697.906,117150813.299,107701424.781,97751921.982,81366149.7358,64815248.0104],\r\n [98061096.2279,107455892.672,104297905.683,100185926.349,82831840.0415,70943170.025],\r\n [89137895.3342,102529524.376,103609158.886,100258967.138,82953357.8248,74711580.7698],\r\n [80061011.5245,99701974.4374,101135778.326,103509334.667,93903836.9186,82575604.803],\r\n [76955476.7623,99204914.2963,100657431.412,105555739.515,97037484.1735,86439016.9643],\r\n [69605396.4523,94038539.7022,99107027.4359,106465379.024,99860594.6244,91198028.5089],\r\n [65217286.435,91077737.2129,97711464.8466,106493430.55,102497916.497,94414439.934],\r\n [56404760.6472,89515576.0369,96725175.6269,110780475.382,106003429.523,99779805.5687],\r\n [57623765.1379,86000000.115,92645901.5832,109963760.39,112042014.351,105580958.636],\r\n [43952333.816,79252453.6185,86299264.174,117994751.33,118933764.105,117810670.231],\r\n [24634373.903,66065001.64,68243438.02,135426575.793,137419433.105,172318869.066],\r\n [18589595.0428,57728776.2495,62320493.2527,139634562.057,152773746.081,223807728.344],\r\n [20594648.2386,59271804.7584,63480011.0556,137984419.731,170575636.626,249672094.732],\r\n [19982219.0805,51425904.8348,62459589.4291,133533308.408,173764569.114,340432929.048],\r\n [14233265.2396,48314855.5797,69876452.1042,118939345.179,202726701.441,782283022.416],\r\n [12050167.2655,41971380.0582,67231664.3917,117242812.869,204972074.627,1193155462.46],\r\n [217614427.542,172388819.341,121628347.075,83816254.3477,55033857.4819,34150040.9715],\r\n [188956032.614,152228600.204,119348410.647,87194122.6816,60562480.3003,39268083.3223],\r\n [181744158.147,148070781.167,115670547.145,89247318.1735,64040594.4522,43685819.4112],\r\n [151073623.188,144854097.547,117506093.143,91800688.1804,68393724.3162,47858125.7734],\r\n [104973486.386,113192497.975,107358293.398,99298184.4158,82854153.6826,66448368.5807],\r\n [96800968.5366,108813789.1,107709745.619,100869902.616,87949796.8523,73853744.7042],\r\n [77542089.7039,100444892.881,104405576.351,103448058.566,92715073.403,80484729.3368],\r\n [73902932.3516,98357005.817,101596272.347,106187268.512,94949640.7439,84977461.0913],\r\n [65723772.4606,92220226.5048,100949356.3,107088570.17,98364839.1687,88907820.7861],\r\n [58227272.214,88096043.6116,97778537.1547,109673326.262,103072681.201,95546867.7228],\r\n [52242736.0392,79021365.3116,92296514.2048,110699401.452,111373663.316,104556413.811],\r\n [42387748.6585,75036578.343,88900875.6779,113953224.692,119871722.227,118650222.998],\r\n [42552145.4285,73277455.5577,86638982.1563,117509435.252,122443225.523,127794645.949],\r\n [29487207.2902,62587561.9928,80747503.8074,122638642.662,133371495.651,146929399.381],\r\n [232212730.923,172748200.813,123164310.855,83234536.1767,52534357.4283,30163940.3295],\r\n [209046363.073,165889951.977,122621699.858,83335081.7221,54798420.2942,34266296.8977],\r\n [175059723.489,158635872.558,119903390.149,84477402.7274,59083638.5898,39711091.9335],\r\n [180976714.043,154287876.699,115600774.565,88075679.1989,61996037.5575,41220965.6938],\r\n [166541063.013,144991639.006,116876672.36,86937102.9577,64578343.8305,44125027.459],\r\n [134791895.785,127292591.696,113389093.855,94065035.7771,71569091.3325,50277016.4088],\r\n [116307285.53,120873545.356,110371130.191,95960676.9701,76880992.7215,61613992.3649],\r\n [93643102.1393,106738439.582,105458128.829,100696412.304,87801584.4699,73494131.1528],\r\n [70155926.5125,92617201.6151,99897419.2984,107979933.81,102133656.856,91712156.019],\r\n [48432684.2664,77640488.3084,95885230.2566,113033574.748,113968272.876,105856099.732],\r\n [44330245.1179,76228877.0172,92090755.5776,115109943.263,116827090.805,111978280.037],\r\n [41986963.3733,76941616.7393,91077765.8441,114116953.114,120770471.227,118076659.132],\r\n [24350677.148,62062462.4579,81391127.5714,120199164.039,139426704.127,139859946.552],\r\n [16566555.6961,51508541.8403,74545214.652,131282172.01,163307573.327,213211499.471],\r\n [15667048.0325,54516055.2198,85268892.8266,137304083.086,180118662.136,244286666.947],\r\n [26899712.5025,47612160.0504,93480391.8501,116366130.415,245905247.734,859551349.959],\r\n [77724573.3068,24522031.096,59371312.1115,85723599.4897,636830700.998,5457044198.07],\r\n [184221616.692,157528964.72,121670502.315,82992698.6482,55715276.2256,34907386.7376],\r\n [186240877.897,146467471.52,118213111.658,86607956.5869,59598204.4652,37143728.2774],\r\n [136253992.631,126603539.187,114298371.853,91497814.6939,72230713.8519,53987276.2465],\r\n [106314561.389,113964562.672,107918869.145,100428267.401,80796162.5065,63503161.2242],\r\n [47356124.0695,77562337.7631,96053464.4237,113941864.156,112215268.984,102384975.424],\r\n [23750150.5736,55415541.0036,87983441.2884,123408442.537,133986521.045,127934773.286],\r\n [17255606.3062,50453390.7123,85294570.3812,132676718.474,154723573.633,163970266.721],\r\n [11155571.6465,38800946.9791,78247709.2722,140346162.545,224168766.021,484901098.72],\r\n [200559738.269,159078279.738,122953889.782,82731894.4139,55184352.7519,34838689.9769],\r\n [165171567.434,140314635.161,117112512.952,86173443.7999,63763344.3168,43066897.3621],\r\n [154588410.824,135316209.281,116328188.041,86979136.0898,64298781.8186,45675697.948],\r\n [162002575.451,135860600.864,116417372.501,87962745.6728,67385382.8884,47394394.2437],\r\n [128859771.183,124587199.774,112922590.213,94837327.0756,77299742.6425,59873845.1031],\r\n [114276325.277,122425104.132,113704531.172,95586394.9436,81568052.7778,66492550.8975],\r\n [69722356.9925,92857115.5751,107702036.034,104686022.445,90162037.5295,75155699.3395],\r\n [53531426.5745,86250467.0279,100677800.573,111415319.959,103181772.44,86715237.9212],\r\n [35730667.9461,66247934.2,96896061.1902,120020733.258,115654081.28,99121977.5028],\r\n [26298204.4428,62679511.988,88463462.5452,124553583.264,136807712.722,111284163.958],\r\n [15272331.1628,44586299.5689,78896976.0433,131072821.633,154407202.907,143787641.777],\r\n [10706035.275,38633176.148,78176970.26,143005159.177,184412033.8,235682483.354],\r\n [9664335.59595,36576257.9713,75767089.7455,138404693.488,226474614.578,437137873.508],\r\n [83175694.5772,88438166.4869,94345688.9479,103217951.644,108653050.69,31193044.2219],\r\n [60303529.1302,74640785.895,85751272.669,113775336.998,126310448.118,143318527.736],\r\n [127382843.883,127391061.218,110617916.138,84726610.041,75952409.0468,75952409.0468],\r\n [56804333.6506,73257905.0076,75274303.5987,103673126.61,105849015.291,113943879.481],\r\n [36338997.8303,65471934.6664,80586441.3589,124557270.448,133214955.509,184503981.16],\r\n ]\r\n var tempidx = parseInt(document.getElementById(\"spec\").value);\r\n var waveidx = parseInt(document.getElementById(\"filter\").value);\r\n \/\/alert(\"tempidx \"+tempidx+\" waveidx \"+waveidx);\r\n \/\/var temp = parseFloat(document.getElementById(\"spec\").value);\r\n var vmag = parseFloat(document.getElementById(\"V\").value);\r\n var air = parseFloat(document.getElementById(\"airmass\").value);\r\n var see = parseFloat(document.getElementById(\"seeing\").value);\r\n var expt = parseFloat(document.getElementById(\"expt\").value);\r\n var binocular = parseFloat(document.getElementById(\"binocular\").value);\r\n var setup = document.getElementById(\"setup\").value;\r\n var filt = document.getElementById(\"filter\").value;\r\n \/\/ flam is filter wavelength in micrometer\r\n var flam;\r\n \/\/ fwhm is the effective size of a pixel, this portion of the planck curve is taken (nm)\r\n var fwhm;\r\n \/\/ CCD efficiency in this band;\r\n var ccd;\r\n \/\/ a value of k' for current filter\r\n var kp;\r\n \/\/ pinhole size in arcsec\r\n var pinhole;\r\n \/\/ M1 size in meters\r\n var m1size;\r\n \/\/ binning is multiplicator for fwhm\r\n var binning;\r\n \/\/ telescope gray transmission \r\n var teltrans;\r\n \/\/ instrument cd-dependent transmission \r\n var insttrans;\r\n \/\/ read-out noise\r\n var ron;\r\n \/\/ width of order in pixel\r\n var npix;\r\n \/\/ LBT measure for kp in 6 cd-wavelengths\r\n var kparr=[0.3035,0.2067,0.1487,0.1180,0.0678,0.0418];\r\n \/\/ setup is fiber size and instrument - PFU,POL,VATT - choice\r\n switch (setup) {\r\n case \"100\":\r\n pinhole=0.74\r\n binning=1.\r\n npix=9.*7.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[0.88,1.35,2.40,3.98,2.84,4.28];\r\n \/\/ effic 2021\r\n insttrans=[0.448,2.015,1.992,1.637,2.278,0.986];\r\n \/\/ effic 2023\r\n insttrans=[1.332,2.658,3.525,4.838,4.897,5.358]; \r\n insttrans_dx=[0.964,2.173,3.703,4.578,4.494,4.37]; \r\n break;\r\n case \"200\":\r\n pinhole=1.5\r\n binning=2.\r\n npix=17.*5.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[0.90,2.00,3.83,4.73,4.93,6.07];\r\n \/\/ effic 2021\r\n \/\/insttrans=[0.545,1.697,2.528,3.554,4.065,4.045];\r\n \/\/ effic 2023\r\n insttrans=[2.645,4.534,7.422,7.868,8.795,8.709]; \r\n insttrans_dx=[1.477,3.072,5.561,5.833,6.687,5.528]; \r\n break;\r\n case \"300\":\r\n pinhole=2.3\r\n binning=5.\r\n npix=35.*3.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[1.62,3.55,5.84,6.87,7.41,6.13];\r\n \/\/ effic 2021\r\n \/\/ insttrans=[1.419,2.064,4.454,3.982,6.469,8.261];\r\n \/\/ effic 2023\r\n insttrans=[3.375,6.827,10.217,11.008,11.314,10.918]; \r\n insttrans_dx=[2.103,4.191,6.933,7.682,8.463,7.68]; \r\n break;\r\n case \"POL\":\r\n pinhole=1.5\r\n binning=2.\r\n npix=17.*5.\r\n m1size=8.4\r\n insttrans=[0.39,1.34,5.10,3.87,7.13,7.61];\r\n insttrans_dx=[0.39,1.34,5.10,3.87,7.13,7.61];\r\n break;\r\n case \"VATT\":\r\n pinhole=7.5\r\n binning=1.\r\n npix=20.*9.\r\n m1size=1.9\r\n insttrans=[0.00,0.50,1.50,4.00,5.00,4.00];\r\n insttrans_dx=[0.00,0.50,1.50,4.00,5.00,4.00];\r\n binocular=0;\r\n document.getElementById(\"binocular\").value=\"0\"; \r\n break;\r\n }\r\n \/\/ filt is wavelength setup: cross-disperser, pixel size, extinction\r\n switch (filt) {\r\n case \"0\":\r\n flam=0.402704;\r\n fwhm=0.000698;\r\n ron = 3.5;\r\n kp=kparr[0];\r\n teltrans=0.01*insttrans[0];\r\n teltrans_dx=0.01*insttrans_dx[0];\r\n break;\r\n case \"1\":\r\n flam=0.450081;\r\n fwhm=0.000781;\r\n ron = 3.5;\r\n kp=kparr[1];\r\n teltrans=0.01*insttrans[1];\r\n teltrans_dx=0.01*insttrans_dx[1];\r\n break;\r\n case \"2\":\r\n flam=0.505877;\r\n fwhm=0.000887;\r\n ron = 3.5;\r\n kp=kparr[2];\r\n teltrans=0.01*insttrans[2];\r\n teltrans_dx=0.01*insttrans_dx[2];\r\n break;\r\n case \"3\":\r\n flam=0.582962;\r\n fwhm=0.000990;\r\n ron = 4.0;\r\n kp=kparr[3];\r\n teltrans=0.01*insttrans[3];\r\n teltrans_dx=0.01*insttrans_dx[3];\r\n break;\r\n case \"4\":\r\n flam=0.687765;\r\n fwhm=0.001182;\r\n ron = 4.0;\r\n kp=kparr[4];\r\n teltrans=0.01*insttrans[4];\r\n teltrans_dx=0.01*insttrans_dx[4];\r\n break;\r\n case \"5\":\r\n flam=0.827176;\r\n fwhm=0.001459;\r\n ron = 4.0;\r\n kp=kparr[5];\r\n teltrans=0.01*insttrans[5];\r\n teltrans_dx=0.01*insttrans_dx[5];\r\n break;\r\n }\r\n \/\/ all losses are considered somewhere else\r\n ccd=1.0;\r\n var vred=vmag+kp*air;\r\n \/\/ zero point at bottom of atmosphere\r\n \/\/var za0 = zeroflux(temp,vred);\r\n \/\/ entrance loss due to pinhole and seeing\r\n var trans = Math.pow(math.erf(pinhole\/(see*1.202)),2)\r\n \/\/ collecting area of a single M1 of LBT\r\n var area = Math.pow(m1size,2)*Math.PI\/4.;\r\n \/\/ number of photons incident at telescope focus, after pinhole\r\n \/\/ var photnr = phot(za0, temp, flam)*fwhm*binning*expt*area*teltrans*trans;\r\n var photnr = fluxarr[tempidx][waveidx]*fwhm*binning*expt*area*teltrans*trans*Math.pow(10,-0.4*vred);\r\n var photnr_dx = fluxarr[tempidx][waveidx]*fwhm*binning*expt*area*teltrans_dx*trans*Math.pow(10,-0.4*vred);\r\n \/\/ number of photons detected.\r\n var signal = photnr*ccd;\r\n var signal_dx = photnr_dx*ccd;\r\n var snratio = signal\/Math.sqrt(signal+npix*Math.pow(ron,2));\r\n var snratio_dx = signal\/Math.sqrt(signal_dx+npix*Math.pow(ron,2));\r\n if (binocular == 1) {\r\n \/\/ snratio = snratio * Math.sqrt(2.)\r\n snratio = Math.sqrt(snratio*snratio + snratio_dx*snratio_dx)\r\n }\r\n snratio = Math.round(snratio)\r\n \/\/alert(\"S: \"+signal+\" npix \"+npix+\" loss \"+loss);\r\n \/\/alert(\"Zero \"+za0+\", K0 \"+photnr);\r\n document.getElementById(\"sn\").value=snratio; \r\n }\r\n<\/script>\r\n<\/head>\r\n<body> \r\n<table>\r\n <tr>\r\n <td align=\"right\">\r\n V mag:\r\n <\/td>\r\n <td>\r\n <input name=\"V\" id=\"V\" type=\"text\" value=\"7.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Spectral type:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"spec\" id=\"spec\"> \r\n <option value=\"0\">O5V<\/option>\r\n <option value=\"1\">O9V<\/option>\r\n <option value=\"2\">B0V<\/option>\r\n <option value=\"3\">B1V<\/option>\r\n <option value=\"4\">B3V<\/option>\r\n <option value=\"5\">B5-7V<\/option>\r\n <option value=\"6\">B8V<\/option>\r\n <option value=\"7\">A0V<\/option>\r\n <option value=\"8\">A2V<\/option>\r\n <option value=\"9\">A3V<\/option>\r\n <option value=\"10\">A5V<\/option>\r\n <option value=\"11\">F0V<\/option>\r\n <option value=\"12\">F2V<\/option>\r\n <option value=\"13\">F5V<\/option>\r\n <option value=\"14\">F8V<\/option>\r\n <option value=\"15\">G0V<\/option>\r\n <option selected value=\"16\">G2V<\/option>\r\n <option value=\"17\">G5V<\/option>\r\n <option value=\"18\">G8V<\/option>\r\n <option value=\"19\">K0V<\/option>\r\n <option value=\"20\">K2V<\/option>\r\n <option value=\"21\">K5V<\/option>\r\n <option value=\"22\">K7V<\/option>\r\n <option value=\"23\">M0V<\/option>\r\n <option value=\"24\">M2V<\/option>\r\n <option value=\"25\">M4V<\/option>\r\n <option value=\"26\">M5V<\/option>\r\n <option value=\"27\">B2IV<\/option>\r\n <option value=\"28\">B6IV<\/option>\r\n <option value=\"29\">A0IV<\/option>\r\n <option value=\"30\">A4-7IV<\/option>\r\n <option value=\"31\">F0-2IV<\/option>\r\n <option value=\"32\">F5IV<\/option>\r\n <option value=\"33\">F8IV<\/option>\r\n <option value=\"34\">G0IV<\/option>\r\n <option value=\"35\">G2IV<\/option>\r\n <option value=\"36\">G5IV<\/option>\r\n <option value=\"37\">G8IV<\/option>\r\n <option value=\"38\">K0IV<\/option>\r\n <option value=\"39\">K1IV<\/option>\r\n <option value=\"40\">K3IV<\/option>\r\n <option value=\"41\">O8III<\/option>\r\n <option value=\"42\">B1-2III<\/option>\r\n <option value=\"43\">B5III<\/option>\r\n <option value=\"44\">B9III<\/option>\r\n <option value=\"45\">A0III<\/option>\r\n <option value=\"46\">A5III<\/option>\r\n <option value=\"47\">F0III<\/option>\r\n <option value=\"48\">F5III<\/option>\r\n <option value=\"49\">G0III<\/option>\r\n <option value=\"50\">G5III<\/option>\r\n <option value=\"51\">G8III<\/option>\r\n <option value=\"52\">K0III<\/option>\r\n <option value=\"53\">K3III<\/option>\r\n <option value=\"54\">K5III<\/option>\r\n <option value=\"55\">M0III<\/option>\r\n <option value=\"56\">M5III<\/option>\r\n <option value=\"57\">M10III<\/option>\r\n <option value=\"58\">B2II<\/option>\r\n <option value=\"59\">B5II<\/option>\r\n <option value=\"60\">F0II<\/option>\r\n <option value=\"61\">F2II<\/option>\r\n <option value=\"62\">G5II<\/option>\r\n <option value=\"63\">K0-1II<\/option>\r\n <option value=\"64\">K3-4II<\/option>\r\n <option value=\"65\">M3II<\/option>\r\n <option value=\"66\">B0I<\/option>\r\n <option value=\"67\">B5I<\/option>\r\n <option value=\"68\">B8I<\/option>\r\n <option value=\"69\">A0I<\/option>\r\n <option value=\"70\">F0I<\/option>\r\n <option value=\"71\">F5I<\/option>\r\n <option value=\"72\">F8I<\/option>\r\n <option value=\"73\">G0I<\/option>\r\n <option value=\"74\">G5I<\/option>\r\n <option value=\"75\">G8I<\/option>\r\n <option value=\"76\">K2I<\/option>\r\n <option value=\"77\">K4I<\/option>\r\n <option value=\"78\">M2I<\/option>\r\n <option value=\"79\">Seyfert1<\/option>\r\n <option value=\"80\">Seyfert2<\/option>\r\n <option value=\"81\">QSO<\/option>\r\n <option value=\"82\">NGC1068<\/option>\r\n\t<option value=\"83\">Liner<\/option>\r\n <\/select>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Airmass:\r\n <\/td>\r\n <td>\r\n <input name=\"airmass\" id=\"airmass\" type=\"text\" value=\"1.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Seeing (arcsec):\r\n <\/td>\r\n <td>\r\n <input name=\"seeing\" id=\"seeing\" type=\"text\" value=\"0.5\" size=6\/>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Exposure time (s):\r\n <\/td>\r\n <td>\r\n <input name=\"expt\" id=\"expt\" type=\"text\" value=\"600.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Cross disperser:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"filter\" id=\"filter\">\r\n\t<option value=\"0\">CD1<\/option>\r\n\t<option value=\"1\">CD2<\/option>\r\n\t<option value=\"2\">CD3<\/option>\r\n\t<option value=\"3\">CD4<\/option>\r\n\t<option selected value=\"4\">CD5<\/option>\r\n\t<option value=\"5\">CD6<\/option>\r\n <\/select>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Setup\/Fiber:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"setup\" id=\"setup\">\r\n\t<option selected value=\"100\">100<\/option>\r\n\t<option value=\"200\">200<\/option>\r\n\t<option value=\"300\">300<\/option>\r\n\t<option value=\"POL\">Polarimeter<\/option>\r\n\t<option value=\"VATT\">VATT<\/option>\r\n <\/select>\r\n <\/td>\r\n <td align=\"right\">\r\n S\/N @ center of CD:\r\n <\/td>\r\n <td>\r\n <input name=\"sn\" id=\"sn\" type=\"text\" disabled size=8\/>\r\n <\/td> \r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Mode:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"binocular\" id=\"binocular\">\r\n\t<option selected value=\"1\">Binocular<\/option>\r\n\t<option value=\"0\">Monocular<\/option>\r\n <\/select>\r\n <\/td>\r\n <td>\r\n <\/td>\r\n <td align=\"left\">\r\n <input type='button' name='exec' Value='Calculate' onClick='snestimate()'><br>\r\n <\/td>\r\n <\/tr>\r\n<\/table>\n<p>PEPSI Exposure Time Calculator v2.10 2021-12-20<\/p>\n\n\n<p>The Exposure time calculator (ETC) estimates the flux from the star by using flux templates from Pickles (1998) and from Francis et al. (1991), scaling them using the V-band vega VEGA flux (Bohlin & Gilliland 2004). The flux is then adjusted by using the V-magnitude supplied, and by applying extinction correction using the airmass and the extinction values from the Multi-Object Double Spectrograph (MODS) instrument manual. According to the selected instrument setup, the correct entrance aperture for each fibre diameter is used (7.5, 0.74, 1.5, 2.3 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m respectively) according to Strassmeier et al. (2007)), and the losses are calculated for that aperture according to the specified seeing value.<\/p>\n<p>The flux is computed for the size of the central pixel in each Cross Disperser (CD), multiplied for the binning if applicable (the 200\u00b5m fiber is 2x binned, the 300\u00b5m fiber is 5x binned). The read-noise of the Charge-Coupled Device (CCD) (on average 3.5 for the blue CCD and 4 for the red CCD; see PEPSI STA1600 10K science CCD camera implementation details) is added to the photon noise, and the size of each slice (20, 9, 17, 35 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m respectively) times the number of slices (9, 7, 5, or 3 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m fibers respectively) is used to determine the number of pixels (see PEPSI image slicer implementation details). For the overall instrument efficiency values are taken from the PEPSI image slicer implementation details. We determined the peak of the efficiency using the 95% quantile for each CD, fiber and telescope. The average value for both telescopes is used in the ETC.<\/p>\n<p>The output is an estimate for the peak (i.e. in the center of the blaze function) Signal to noise ratio (SNR) of the specified cross-disperser for an individual spectrum. As of Oct 2023, the efficiencies for SX and DX are calculated separately since they differ by up to 30\\% (DX having lower throughput). When using PEPSI in binocular mode, the SNR is the geometric sum for the two sides, in monocular mode SX values are used. For the polarimeter, the Foster prism splits the light into two, we give the value of the sum of these two spectra. As there is only one fiber from the Vatican Advanced Technology Telescope (VATT), the monocular mode is always used in that setting.<\/p>\n<h5>References<\/h5>\n<ul>\n<li>Bohlin, R. C. & Gilliland, R. L. 2004, AJ, 127, 3508<\/li>\n<li>Francis, P. J., Hewett, P. C., Foltz, C. B., et al. 1991, ApJ, 373, 465<\/li>\n<li>Pickles, A. J. 1998, PASP, 110, 863<\/li>\n<li>Strassmeier, K. G., Woche, M., Andersen, M., & Ilyin, I. 2007, Astronomische Nachrichten, 328, 627<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>PEPSI Exposure Time Calculator v2.10 2021-12-20 The Exposure time calculator (ETC) estimates the flux from the star by using flux templates from Pickles (1998) and from Francis et al. (1991), scaling them using the V-band vega VEGA flux (Bohlin & Gilliland 2004). The flux is then adjusted by using the V-magnitude supplied, and by applying … <a href=\"https:\/\/pepsi.aip.de\/?page_id=1410\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Exposure Time Calculator<\/span> <span class=\"meta-nav\">→<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1410","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1410"}],"version-history":[{"count":27,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410\/revisions"}],"predecessor-version":[{"id":2172,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410\/revisions\/2172"}],"wp:attachment":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1410"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":1410,"date":"2020-01-17T13:02:25","date_gmt":"2020-01-17T12:02:25","guid":{"rendered":"https:\/\/pepsi.aip.de\/?page_id=1410"},"modified":"2023-10-10T12:35:28","modified_gmt":"2023-10-10T11:35:28","slug":"exposure-time-calculator","status":"publish","type":"page","link":"https:\/\/pepsi.aip.de\/?page_id=1410","title":{"rendered":"Exposure Time Calculator"},"content":{"rendered":"\r\nPEPSI Exposure Time Calculator (ETC)<\/title>\r\n<script type=\"text\/javascript\" src=\"https:\/\/pepsi.aip.de\/etc\/math.min.js\"><\/script>\r\n<script type=\"text\/javascript\">\r\n function snestimate() {\r\n var fluxarr = [\r\n [239593039.763,178543473.813,124031554.257,82534178.9555,52094588.3886,30216798.7116],\r\n [224137694.103,172205034.458,126093669.89,80045933.2903,51523158.0048,30126736.1341],\r\n [228955744.058,174893335.89,123225191.932,83093894.2227,53409615.9756,31982647.2655],\r\n [203867603.322,163612745.223,121765478.951,84705239.0309,54203841.1893,34916553.3623],\r\n [193000258.246,159633040.67,120739509.738,83739958.6425,56950404.9026,37220541.4696],\r\n [196964790.184,156444685.295,119223858.616,85247685.164,60502251.1293,40693294.6208],\r\n [185401043.818,147695755.167,113467540.659,87920455.11,60709980.127,42093478.8237],\r\n [167909073.769,146713180.85,116465787.385,89571584.9871,64926699.746,43691869.1895],\r\n [167158116.581,145482676.804,114951518.904,88475523.2607,65030701.9542,46120088.6093],\r\n [157760706.291,137836455.92,113379915.298,91641365.1536,68924700.2428,48698033.483],\r\n [143607150.179,127875584.892,112520771.519,93223216.4379,70387887.7272,50546712.6645],\r\n [112483697.906,117150813.299,107701424.781,97751921.982,81366149.7358,64815248.0104],\r\n [98061096.2279,107455892.672,104297905.683,100185926.349,82831840.0415,70943170.025],\r\n [89137895.3342,102529524.376,103609158.886,100258967.138,82953357.8248,74711580.7698],\r\n [80061011.5245,99701974.4374,101135778.326,103509334.667,93903836.9186,82575604.803],\r\n [76955476.7623,99204914.2963,100657431.412,105555739.515,97037484.1735,86439016.9643],\r\n [69605396.4523,94038539.7022,99107027.4359,106465379.024,99860594.6244,91198028.5089],\r\n [65217286.435,91077737.2129,97711464.8466,106493430.55,102497916.497,94414439.934],\r\n [56404760.6472,89515576.0369,96725175.6269,110780475.382,106003429.523,99779805.5687],\r\n [57623765.1379,86000000.115,92645901.5832,109963760.39,112042014.351,105580958.636],\r\n [43952333.816,79252453.6185,86299264.174,117994751.33,118933764.105,117810670.231],\r\n [24634373.903,66065001.64,68243438.02,135426575.793,137419433.105,172318869.066],\r\n [18589595.0428,57728776.2495,62320493.2527,139634562.057,152773746.081,223807728.344],\r\n [20594648.2386,59271804.7584,63480011.0556,137984419.731,170575636.626,249672094.732],\r\n [19982219.0805,51425904.8348,62459589.4291,133533308.408,173764569.114,340432929.048],\r\n [14233265.2396,48314855.5797,69876452.1042,118939345.179,202726701.441,782283022.416],\r\n [12050167.2655,41971380.0582,67231664.3917,117242812.869,204972074.627,1193155462.46],\r\n [217614427.542,172388819.341,121628347.075,83816254.3477,55033857.4819,34150040.9715],\r\n [188956032.614,152228600.204,119348410.647,87194122.6816,60562480.3003,39268083.3223],\r\n [181744158.147,148070781.167,115670547.145,89247318.1735,64040594.4522,43685819.4112],\r\n [151073623.188,144854097.547,117506093.143,91800688.1804,68393724.3162,47858125.7734],\r\n [104973486.386,113192497.975,107358293.398,99298184.4158,82854153.6826,66448368.5807],\r\n [96800968.5366,108813789.1,107709745.619,100869902.616,87949796.8523,73853744.7042],\r\n [77542089.7039,100444892.881,104405576.351,103448058.566,92715073.403,80484729.3368],\r\n [73902932.3516,98357005.817,101596272.347,106187268.512,94949640.7439,84977461.0913],\r\n [65723772.4606,92220226.5048,100949356.3,107088570.17,98364839.1687,88907820.7861],\r\n [58227272.214,88096043.6116,97778537.1547,109673326.262,103072681.201,95546867.7228],\r\n [52242736.0392,79021365.3116,92296514.2048,110699401.452,111373663.316,104556413.811],\r\n [42387748.6585,75036578.343,88900875.6779,113953224.692,119871722.227,118650222.998],\r\n [42552145.4285,73277455.5577,86638982.1563,117509435.252,122443225.523,127794645.949],\r\n [29487207.2902,62587561.9928,80747503.8074,122638642.662,133371495.651,146929399.381],\r\n [232212730.923,172748200.813,123164310.855,83234536.1767,52534357.4283,30163940.3295],\r\n [209046363.073,165889951.977,122621699.858,83335081.7221,54798420.2942,34266296.8977],\r\n [175059723.489,158635872.558,119903390.149,84477402.7274,59083638.5898,39711091.9335],\r\n [180976714.043,154287876.699,115600774.565,88075679.1989,61996037.5575,41220965.6938],\r\n [166541063.013,144991639.006,116876672.36,86937102.9577,64578343.8305,44125027.459],\r\n [134791895.785,127292591.696,113389093.855,94065035.7771,71569091.3325,50277016.4088],\r\n [116307285.53,120873545.356,110371130.191,95960676.9701,76880992.7215,61613992.3649],\r\n [93643102.1393,106738439.582,105458128.829,100696412.304,87801584.4699,73494131.1528],\r\n [70155926.5125,92617201.6151,99897419.2984,107979933.81,102133656.856,91712156.019],\r\n [48432684.2664,77640488.3084,95885230.2566,113033574.748,113968272.876,105856099.732],\r\n [44330245.1179,76228877.0172,92090755.5776,115109943.263,116827090.805,111978280.037],\r\n [41986963.3733,76941616.7393,91077765.8441,114116953.114,120770471.227,118076659.132],\r\n [24350677.148,62062462.4579,81391127.5714,120199164.039,139426704.127,139859946.552],\r\n [16566555.6961,51508541.8403,74545214.652,131282172.01,163307573.327,213211499.471],\r\n [15667048.0325,54516055.2198,85268892.8266,137304083.086,180118662.136,244286666.947],\r\n [26899712.5025,47612160.0504,93480391.8501,116366130.415,245905247.734,859551349.959],\r\n [77724573.3068,24522031.096,59371312.1115,85723599.4897,636830700.998,5457044198.07],\r\n [184221616.692,157528964.72,121670502.315,82992698.6482,55715276.2256,34907386.7376],\r\n [186240877.897,146467471.52,118213111.658,86607956.5869,59598204.4652,37143728.2774],\r\n [136253992.631,126603539.187,114298371.853,91497814.6939,72230713.8519,53987276.2465],\r\n [106314561.389,113964562.672,107918869.145,100428267.401,80796162.5065,63503161.2242],\r\n [47356124.0695,77562337.7631,96053464.4237,113941864.156,112215268.984,102384975.424],\r\n [23750150.5736,55415541.0036,87983441.2884,123408442.537,133986521.045,127934773.286],\r\n [17255606.3062,50453390.7123,85294570.3812,132676718.474,154723573.633,163970266.721],\r\n [11155571.6465,38800946.9791,78247709.2722,140346162.545,224168766.021,484901098.72],\r\n [200559738.269,159078279.738,122953889.782,82731894.4139,55184352.7519,34838689.9769],\r\n [165171567.434,140314635.161,117112512.952,86173443.7999,63763344.3168,43066897.3621],\r\n [154588410.824,135316209.281,116328188.041,86979136.0898,64298781.8186,45675697.948],\r\n [162002575.451,135860600.864,116417372.501,87962745.6728,67385382.8884,47394394.2437],\r\n [128859771.183,124587199.774,112922590.213,94837327.0756,77299742.6425,59873845.1031],\r\n [114276325.277,122425104.132,113704531.172,95586394.9436,81568052.7778,66492550.8975],\r\n [69722356.9925,92857115.5751,107702036.034,104686022.445,90162037.5295,75155699.3395],\r\n [53531426.5745,86250467.0279,100677800.573,111415319.959,103181772.44,86715237.9212],\r\n [35730667.9461,66247934.2,96896061.1902,120020733.258,115654081.28,99121977.5028],\r\n [26298204.4428,62679511.988,88463462.5452,124553583.264,136807712.722,111284163.958],\r\n [15272331.1628,44586299.5689,78896976.0433,131072821.633,154407202.907,143787641.777],\r\n [10706035.275,38633176.148,78176970.26,143005159.177,184412033.8,235682483.354],\r\n [9664335.59595,36576257.9713,75767089.7455,138404693.488,226474614.578,437137873.508],\r\n [83175694.5772,88438166.4869,94345688.9479,103217951.644,108653050.69,31193044.2219],\r\n [60303529.1302,74640785.895,85751272.669,113775336.998,126310448.118,143318527.736],\r\n [127382843.883,127391061.218,110617916.138,84726610.041,75952409.0468,75952409.0468],\r\n [56804333.6506,73257905.0076,75274303.5987,103673126.61,105849015.291,113943879.481],\r\n [36338997.8303,65471934.6664,80586441.3589,124557270.448,133214955.509,184503981.16],\r\n ]\r\n var tempidx = parseInt(document.getElementById(\"spec\").value);\r\n var waveidx = parseInt(document.getElementById(\"filter\").value);\r\n \/\/alert(\"tempidx \"+tempidx+\" waveidx \"+waveidx);\r\n \/\/var temp = parseFloat(document.getElementById(\"spec\").value);\r\n var vmag = parseFloat(document.getElementById(\"V\").value);\r\n var air = parseFloat(document.getElementById(\"airmass\").value);\r\n var see = parseFloat(document.getElementById(\"seeing\").value);\r\n var expt = parseFloat(document.getElementById(\"expt\").value);\r\n var binocular = parseFloat(document.getElementById(\"binocular\").value);\r\n var setup = document.getElementById(\"setup\").value;\r\n var filt = document.getElementById(\"filter\").value;\r\n \/\/ flam is filter wavelength in micrometer\r\n var flam;\r\n \/\/ fwhm is the effective size of a pixel, this portion of the planck curve is taken (nm)\r\n var fwhm;\r\n \/\/ CCD efficiency in this band;\r\n var ccd;\r\n \/\/ a value of k' for current filter\r\n var kp;\r\n \/\/ pinhole size in arcsec\r\n var pinhole;\r\n \/\/ M1 size in meters\r\n var m1size;\r\n \/\/ binning is multiplicator for fwhm\r\n var binning;\r\n \/\/ telescope gray transmission \r\n var teltrans;\r\n \/\/ instrument cd-dependent transmission \r\n var insttrans;\r\n \/\/ read-out noise\r\n var ron;\r\n \/\/ width of order in pixel\r\n var npix;\r\n \/\/ LBT measure for kp in 6 cd-wavelengths\r\n var kparr=[0.3035,0.2067,0.1487,0.1180,0.0678,0.0418];\r\n \/\/ setup is fiber size and instrument - PFU,POL,VATT - choice\r\n switch (setup) {\r\n case \"100\":\r\n pinhole=0.74\r\n binning=1.\r\n npix=9.*7.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[0.88,1.35,2.40,3.98,2.84,4.28];\r\n \/\/ effic 2021\r\n insttrans=[0.448,2.015,1.992,1.637,2.278,0.986];\r\n \/\/ effic 2023\r\n insttrans=[1.332,2.658,3.525,4.838,4.897,5.358]; \r\n insttrans_dx=[0.964,2.173,3.703,4.578,4.494,4.37]; \r\n break;\r\n case \"200\":\r\n pinhole=1.5\r\n binning=2.\r\n npix=17.*5.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[0.90,2.00,3.83,4.73,4.93,6.07];\r\n \/\/ effic 2021\r\n \/\/insttrans=[0.545,1.697,2.528,3.554,4.065,4.045];\r\n \/\/ effic 2023\r\n insttrans=[2.645,4.534,7.422,7.868,8.795,8.709]; \r\n insttrans_dx=[1.477,3.072,5.561,5.833,6.687,5.528]; \r\n break;\r\n case \"300\":\r\n pinhole=2.3\r\n binning=5.\r\n npix=35.*3.\r\n m1size=8.4\r\n \/\/ effic 2019\r\n \/\/ insttrans=[1.62,3.55,5.84,6.87,7.41,6.13];\r\n \/\/ effic 2021\r\n \/\/ insttrans=[1.419,2.064,4.454,3.982,6.469,8.261];\r\n \/\/ effic 2023\r\n insttrans=[3.375,6.827,10.217,11.008,11.314,10.918]; \r\n insttrans_dx=[2.103,4.191,6.933,7.682,8.463,7.68]; \r\n break;\r\n case \"POL\":\r\n pinhole=1.5\r\n binning=2.\r\n npix=17.*5.\r\n m1size=8.4\r\n insttrans=[0.39,1.34,5.10,3.87,7.13,7.61];\r\n insttrans_dx=[0.39,1.34,5.10,3.87,7.13,7.61];\r\n break;\r\n case \"VATT\":\r\n pinhole=7.5\r\n binning=1.\r\n npix=20.*9.\r\n m1size=1.9\r\n insttrans=[0.00,0.50,1.50,4.00,5.00,4.00];\r\n insttrans_dx=[0.00,0.50,1.50,4.00,5.00,4.00];\r\n binocular=0;\r\n document.getElementById(\"binocular\").value=\"0\"; \r\n break;\r\n }\r\n \/\/ filt is wavelength setup: cross-disperser, pixel size, extinction\r\n switch (filt) {\r\n case \"0\":\r\n flam=0.402704;\r\n fwhm=0.000698;\r\n ron = 3.5;\r\n kp=kparr[0];\r\n teltrans=0.01*insttrans[0];\r\n teltrans_dx=0.01*insttrans_dx[0];\r\n break;\r\n case \"1\":\r\n flam=0.450081;\r\n fwhm=0.000781;\r\n ron = 3.5;\r\n kp=kparr[1];\r\n teltrans=0.01*insttrans[1];\r\n teltrans_dx=0.01*insttrans_dx[1];\r\n break;\r\n case \"2\":\r\n flam=0.505877;\r\n fwhm=0.000887;\r\n ron = 3.5;\r\n kp=kparr[2];\r\n teltrans=0.01*insttrans[2];\r\n teltrans_dx=0.01*insttrans_dx[2];\r\n break;\r\n case \"3\":\r\n flam=0.582962;\r\n fwhm=0.000990;\r\n ron = 4.0;\r\n kp=kparr[3];\r\n teltrans=0.01*insttrans[3];\r\n teltrans_dx=0.01*insttrans_dx[3];\r\n break;\r\n case \"4\":\r\n flam=0.687765;\r\n fwhm=0.001182;\r\n ron = 4.0;\r\n kp=kparr[4];\r\n teltrans=0.01*insttrans[4];\r\n teltrans_dx=0.01*insttrans_dx[4];\r\n break;\r\n case \"5\":\r\n flam=0.827176;\r\n fwhm=0.001459;\r\n ron = 4.0;\r\n kp=kparr[5];\r\n teltrans=0.01*insttrans[5];\r\n teltrans_dx=0.01*insttrans_dx[5];\r\n break;\r\n }\r\n \/\/ all losses are considered somewhere else\r\n ccd=1.0;\r\n var vred=vmag+kp*air;\r\n \/\/ zero point at bottom of atmosphere\r\n \/\/var za0 = zeroflux(temp,vred);\r\n \/\/ entrance loss due to pinhole and seeing\r\n var trans = Math.pow(math.erf(pinhole\/(see*1.202)),2)\r\n \/\/ collecting area of a single M1 of LBT\r\n var area = Math.pow(m1size,2)*Math.PI\/4.;\r\n \/\/ number of photons incident at telescope focus, after pinhole\r\n \/\/ var photnr = phot(za0, temp, flam)*fwhm*binning*expt*area*teltrans*trans;\r\n var photnr = fluxarr[tempidx][waveidx]*fwhm*binning*expt*area*teltrans*trans*Math.pow(10,-0.4*vred);\r\n var photnr_dx = fluxarr[tempidx][waveidx]*fwhm*binning*expt*area*teltrans_dx*trans*Math.pow(10,-0.4*vred);\r\n \/\/ number of photons detected.\r\n var signal = photnr*ccd;\r\n var signal_dx = photnr_dx*ccd;\r\n var snratio = signal\/Math.sqrt(signal+npix*Math.pow(ron,2));\r\n var snratio_dx = signal\/Math.sqrt(signal_dx+npix*Math.pow(ron,2));\r\n if (binocular == 1) {\r\n \/\/ snratio = snratio * Math.sqrt(2.)\r\n snratio = Math.sqrt(snratio*snratio + snratio_dx*snratio_dx)\r\n }\r\n snratio = Math.round(snratio)\r\n \/\/alert(\"S: \"+signal+\" npix \"+npix+\" loss \"+loss);\r\n \/\/alert(\"Zero \"+za0+\", K0 \"+photnr);\r\n document.getElementById(\"sn\").value=snratio; \r\n }\r\n<\/script>\r\n<\/head>\r\n<body> \r\n<table>\r\n <tr>\r\n <td align=\"right\">\r\n V mag:\r\n <\/td>\r\n <td>\r\n <input name=\"V\" id=\"V\" type=\"text\" value=\"7.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Spectral type:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"spec\" id=\"spec\"> \r\n <option value=\"0\">O5V<\/option>\r\n <option value=\"1\">O9V<\/option>\r\n <option value=\"2\">B0V<\/option>\r\n <option value=\"3\">B1V<\/option>\r\n <option value=\"4\">B3V<\/option>\r\n <option value=\"5\">B5-7V<\/option>\r\n <option value=\"6\">B8V<\/option>\r\n <option value=\"7\">A0V<\/option>\r\n <option value=\"8\">A2V<\/option>\r\n <option value=\"9\">A3V<\/option>\r\n <option value=\"10\">A5V<\/option>\r\n <option value=\"11\">F0V<\/option>\r\n <option value=\"12\">F2V<\/option>\r\n <option value=\"13\">F5V<\/option>\r\n <option value=\"14\">F8V<\/option>\r\n <option value=\"15\">G0V<\/option>\r\n <option selected value=\"16\">G2V<\/option>\r\n <option value=\"17\">G5V<\/option>\r\n <option value=\"18\">G8V<\/option>\r\n <option value=\"19\">K0V<\/option>\r\n <option value=\"20\">K2V<\/option>\r\n <option value=\"21\">K5V<\/option>\r\n <option value=\"22\">K7V<\/option>\r\n <option value=\"23\">M0V<\/option>\r\n <option value=\"24\">M2V<\/option>\r\n <option value=\"25\">M4V<\/option>\r\n <option value=\"26\">M5V<\/option>\r\n <option value=\"27\">B2IV<\/option>\r\n <option value=\"28\">B6IV<\/option>\r\n <option value=\"29\">A0IV<\/option>\r\n <option value=\"30\">A4-7IV<\/option>\r\n <option value=\"31\">F0-2IV<\/option>\r\n <option value=\"32\">F5IV<\/option>\r\n <option value=\"33\">F8IV<\/option>\r\n <option value=\"34\">G0IV<\/option>\r\n <option value=\"35\">G2IV<\/option>\r\n <option value=\"36\">G5IV<\/option>\r\n <option value=\"37\">G8IV<\/option>\r\n <option value=\"38\">K0IV<\/option>\r\n <option value=\"39\">K1IV<\/option>\r\n <option value=\"40\">K3IV<\/option>\r\n <option value=\"41\">O8III<\/option>\r\n <option value=\"42\">B1-2III<\/option>\r\n <option value=\"43\">B5III<\/option>\r\n <option value=\"44\">B9III<\/option>\r\n <option value=\"45\">A0III<\/option>\r\n <option value=\"46\">A5III<\/option>\r\n <option value=\"47\">F0III<\/option>\r\n <option value=\"48\">F5III<\/option>\r\n <option value=\"49\">G0III<\/option>\r\n <option value=\"50\">G5III<\/option>\r\n <option value=\"51\">G8III<\/option>\r\n <option value=\"52\">K0III<\/option>\r\n <option value=\"53\">K3III<\/option>\r\n <option value=\"54\">K5III<\/option>\r\n <option value=\"55\">M0III<\/option>\r\n <option value=\"56\">M5III<\/option>\r\n <option value=\"57\">M10III<\/option>\r\n <option value=\"58\">B2II<\/option>\r\n <option value=\"59\">B5II<\/option>\r\n <option value=\"60\">F0II<\/option>\r\n <option value=\"61\">F2II<\/option>\r\n <option value=\"62\">G5II<\/option>\r\n <option value=\"63\">K0-1II<\/option>\r\n <option value=\"64\">K3-4II<\/option>\r\n <option value=\"65\">M3II<\/option>\r\n <option value=\"66\">B0I<\/option>\r\n <option value=\"67\">B5I<\/option>\r\n <option value=\"68\">B8I<\/option>\r\n <option value=\"69\">A0I<\/option>\r\n <option value=\"70\">F0I<\/option>\r\n <option value=\"71\">F5I<\/option>\r\n <option value=\"72\">F8I<\/option>\r\n <option value=\"73\">G0I<\/option>\r\n <option value=\"74\">G5I<\/option>\r\n <option value=\"75\">G8I<\/option>\r\n <option value=\"76\">K2I<\/option>\r\n <option value=\"77\">K4I<\/option>\r\n <option value=\"78\">M2I<\/option>\r\n <option value=\"79\">Seyfert1<\/option>\r\n <option value=\"80\">Seyfert2<\/option>\r\n <option value=\"81\">QSO<\/option>\r\n <option value=\"82\">NGC1068<\/option>\r\n\t<option value=\"83\">Liner<\/option>\r\n <\/select>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Airmass:\r\n <\/td>\r\n <td>\r\n <input name=\"airmass\" id=\"airmass\" type=\"text\" value=\"1.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Seeing (arcsec):\r\n <\/td>\r\n <td>\r\n <input name=\"seeing\" id=\"seeing\" type=\"text\" value=\"0.5\" size=6\/>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Exposure time (s):\r\n <\/td>\r\n <td>\r\n <input name=\"expt\" id=\"expt\" type=\"text\" value=\"600.0\" size=6\/>\r\n <\/td>\r\n <td align=\"right\">\r\n Cross disperser:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"filter\" id=\"filter\">\r\n\t<option value=\"0\">CD1<\/option>\r\n\t<option value=\"1\">CD2<\/option>\r\n\t<option value=\"2\">CD3<\/option>\r\n\t<option value=\"3\">CD4<\/option>\r\n\t<option selected value=\"4\">CD5<\/option>\r\n\t<option value=\"5\">CD6<\/option>\r\n <\/select>\r\n <\/td>\r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Setup\/Fiber:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"setup\" id=\"setup\">\r\n\t<option selected value=\"100\">100<\/option>\r\n\t<option value=\"200\">200<\/option>\r\n\t<option value=\"300\">300<\/option>\r\n\t<option value=\"POL\">Polarimeter<\/option>\r\n\t<option value=\"VATT\">VATT<\/option>\r\n <\/select>\r\n <\/td>\r\n <td align=\"right\">\r\n S\/N @ center of CD:\r\n <\/td>\r\n <td>\r\n <input name=\"sn\" id=\"sn\" type=\"text\" disabled size=8\/>\r\n <\/td> \r\n <\/tr>\r\n <tr>\r\n <td align=\"right\">\r\n Mode:\r\n <\/td>\r\n <td>\r\n <select size=\"1\" name=\"binocular\" id=\"binocular\">\r\n\t<option selected value=\"1\">Binocular<\/option>\r\n\t<option value=\"0\">Monocular<\/option>\r\n <\/select>\r\n <\/td>\r\n <td>\r\n <\/td>\r\n <td align=\"left\">\r\n <input type='button' name='exec' Value='Calculate' onClick='snestimate()'><br>\r\n <\/td>\r\n <\/tr>\r\n<\/table>\n<p>PEPSI Exposure Time Calculator v2.10 2021-12-20<\/p>\n\n\n<p>The Exposure time calculator (ETC) estimates the flux from the star by using flux templates from Pickles (1998) and from Francis et al. (1991), scaling them using the V-band vega VEGA flux (Bohlin & Gilliland 2004). The flux is then adjusted by using the V-magnitude supplied, and by applying extinction correction using the airmass and the extinction values from the Multi-Object Double Spectrograph (MODS) instrument manual. According to the selected instrument setup, the correct entrance aperture for each fibre diameter is used (7.5, 0.74, 1.5, 2.3 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m respectively) according to Strassmeier et al. (2007)), and the losses are calculated for that aperture according to the specified seeing value.<\/p>\n<p>The flux is computed for the size of the central pixel in each Cross Disperser (CD), multiplied for the binning if applicable (the 200\u00b5m fiber is 2x binned, the 300\u00b5m fiber is 5x binned). The read-noise of the Charge-Coupled Device (CCD) (on average 3.5 for the blue CCD and 4 for the red CCD; see PEPSI STA1600 10K science CCD camera implementation details) is added to the photon noise, and the size of each slice (20, 9, 17, 35 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m respectively) times the number of slices (9, 7, 5, or 3 for VATT, 100\u00b5m, 200\u00b5m\/Polarimeter, 300\u00b5m fibers respectively) is used to determine the number of pixels (see PEPSI image slicer implementation details). For the overall instrument efficiency values are taken from the PEPSI image slicer implementation details. We determined the peak of the efficiency using the 95% quantile for each CD, fiber and telescope. The average value for both telescopes is used in the ETC.<\/p>\n<p>The output is an estimate for the peak (i.e. in the center of the blaze function) Signal to noise ratio (SNR) of the specified cross-disperser for an individual spectrum. As of Oct 2023, the efficiencies for SX and DX are calculated separately since they differ by up to 30\\% (DX having lower throughput). When using PEPSI in binocular mode, the SNR is the geometric sum for the two sides, in monocular mode SX values are used. For the polarimeter, the Foster prism splits the light into two, we give the value of the sum of these two spectra. As there is only one fiber from the Vatican Advanced Technology Telescope (VATT), the monocular mode is always used in that setting.<\/p>\n<h5>References<\/h5>\n<ul>\n<li>Bohlin, R. C. & Gilliland, R. L. 2004, AJ, 127, 3508<\/li>\n<li>Francis, P. J., Hewett, P. C., Foltz, C. B., et al. 1991, ApJ, 373, 465<\/li>\n<li>Pickles, A. J. 1998, PASP, 110, 863<\/li>\n<li>Strassmeier, K. G., Woche, M., Andersen, M., & Ilyin, I. 2007, Astronomische Nachrichten, 328, 627<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>PEPSI Exposure Time Calculator v2.10 2021-12-20 The Exposure time calculator (ETC) estimates the flux from the star by using flux templates from Pickles (1998) and from Francis et al. (1991), scaling them using the V-band vega VEGA flux (Bohlin & Gilliland 2004). The flux is then adjusted by using the V-magnitude supplied, and by applying … <a href=\"https:\/\/pepsi.aip.de\/?page_id=1410\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Exposure Time Calculator<\/span> <span class=\"meta-nav\">→<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1410","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1410"}],"version-history":[{"count":27,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410\/revisions"}],"predecessor-version":[{"id":2172,"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=\/wp\/v2\/pages\/1410\/revisions\/2172"}],"wp:attachment":[{"href":"https:\/\/pepsi.aip.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1410"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}