Validation of Foreground Emission Model using GALEX Medium Observations  

作　　者：Nimmi Narayanan Shivashankar S.Menon N.V.Sujatha 

机构地区：[1]Department of Physics,St.Xavier's College for Women,Aluva 683101,India [2]Department of Physics,Sree Sankara College,Kalady,Ernakulam 683574,India [3]CSIS,BITS Pilani K.K.Birla Goa Campus,Zuarinagar,Goa 403726,India

出　　处：《Research in Astronomy and Astrophysics》2023年第6期228-237,共10页天文和天体物理学研究（英文版）

基　　金：NASA's GALEX program;STScI is operated by the Association of Universities for Research in Astronomy,Inc.,under NASA contract NAS5-26555;Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NNX09AF08G and by other grants and contracts;the support of DST-FIST。

摘　　要：The study of diffuse ultraviolet(UV)background radiation is vital in the investigation of stellar and galactic evolution.Space-based UV observations are comprised of both foreground and background radiations.The foreground emission in an observation is a result of solar contamination in the direction of observation.In our previous work,we modeled airglow(one of the major constituents of the foreground emission)as a function of10.7 cm Solar Flux and Sun Angle with great accuracy using GALEX deep observations.We adopt a similar methodology to validate the obtained model and run equivalent experiments here using far-UV(FUV)and nearUV(NUV)GALEX medium imaging surveys(MIS)with a total exposure time greater than 3300 s.We obtained a predictive model having excellent compatibility with the earlier model.Our analysis shows that the total foreground emission varies between 59 and 295 photon units in FUV whereas in NUV,it varies between 671 and1195 photon units depending upon the date and time of observation.We also noticed a strong correlation between the background emission and optical depth both in FUV and NUV,especially in the low density regions.This clearly indicates that the major contributor in diffuse background radiation is the starlight scattered by interstellar dust grains.

关 键 词：instrumentation:detectors Sun:activity ultraviolet:ISM atmospheric effects 

分 类 号：P15[天文地球—天文学]