Spectral atlases of the Sun from 3980 to 7100 Å at the center and at the limb

Abstract

In this work, we present digital and graphical atlases of spectra of both the solar disk-center and of the limb near the Solar poles using data taken at the UTS−IAP & RIAAM (the University of Tabriz Siderostat, telescope and spectrograph jointly developed with the Institut d'Astrophysique de Paris and Research Institute for Astronomy and Astrophysics of Maragha). High resolution and high signal-to-noise ratio (SNR) CCDslit spectra of the sun for 2 different parts of the disk, namely for µ = 1.0 (solar center) & for µ = 0.3 (solar limb) are provided and discussed. While there are several spectral atlases of the solar disk-center, this is the first spectral atlas ever produced for the solar limb at this spectral range. The resolution of the spectra is about R ∼ 70 000 (∆λ ∼ 0.09Å) with the signal-tonoise ratio (SNR) of 400−600. The full atlas covers the 3980 to 7100Å spectral regions and contains 44 pages with three partial spectra of the solar spectrum put on each page to make it compact. The difference spectrum of the normalized solar disk-center and the solar limb is also included in the graphic presentation of the atlas to show the difference of line profiles, including far wings. The identification of the most significant solar lines is included in the graphic presentation of the atlas. Telluric lines are producing a definite signature on the difference spectra which is easy to notice. At the end of this paper we present only two sample pages of the whole atlas while the graphic presentation of the whole atlas along with its ASCII file can be accessed via the ftp server of the CDS in Strasbourg via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via this link 1 .

Ghostly Strong Lyα Absorbers: Tracers of Gas Flows in the Close Vicinity of Quasars?

“…However, since the DLA trough in a ghostly DLA is almost fully filled with the leaked emission from the BLR (Fathivavsari et al 2017), such methods are not well suited for finding these DLAs. We, therefore, use the metal template technique (Herbert-Fort et al 2006;Fathivavsari et al 2014) to search for ghostly DLAs in SDSS-BOSS spectra. The metal template technique identifies DLA candidates by cross-correlating the observed spectra with an absorption template made up of several strong metal absorption lines generally detected in DLAs.…”

Fraunhofer lines in the transition from the center to the limb of the solar disk

“…2.  ðàáîòå [17] ïðåäñòàâëåí àòëàñ öåíòðà ñîëíå÷íîãî äèñêà è ñîë -íå÷íîãî ëèìáà âáëèçè îäíîãî èç ïîëþñîâ (m = 0.3). Íàáëþäåíèÿ ïðîâî äèëèñü â èþíå (öåíòð äèñêà) è íîÿáðå (ëèìá) 2013 ã. íà ñè äåðîñòàòå óíèâåðñèòåòà Òàáðèç ïðè îòñóòñòâèè â îáëàñòè ùåëè ïÿòåí è àêòèâíûõ îáëàñòåé.…”

“…Àòëàñ îõâàòûâàåò äèàïàçîí äëèí âîëí l = = 398.0...710.0 íì. Ê ñîaeàëåíèþ, àòëàñû [17,29] íå ïîçâîëÿþò äåòàëüíî èçó÷èòü èçìå íåíèÿ ëèíèé ïðè ïåðåõîäå îò öåíòðà ê êðàþ ñîëíå÷íîãî äèñêà. Öåííîñòü ýòèõ ðàáîò â òîì, ÷òî îíè äàþò âîçìîaeíîñòü ñîïîñòàâèòü îãðîìíîå êîëè÷åñòâî ñïåêòðàëüíûõ ëèíèé â öåíòðå è íà êðàþ äèñêà Ñîëíöà, îòêàëèáðîâàòü íàáëþäåíèÿ, èçó÷èòü òåíäåíöèè èçìåíåíèÿ ê êðàþ äëÿ ãðóïï ëèíèé è ò. ä. Îòíîøåíèå ñïåêòðîâ, ïîëó÷åííûõ â öåíò ðå è âáëèçè êðàÿ äèñêà, èìååò ñëîaeíóþ è áîãàòóþ ñòðóêòóðó è, ñî ãëàñíî [29], äîñòîéíî áûòü íàçâàíûì òðåòüèì ñîëíå÷íûì ñïåêòðîì.…”

“…Ïðè ïîñòðîåíèè ðèñóíêà ñïåêòðû íà ëèìáå íåñêîëüêî ñìåùàëèñü â ôèîëåòîâóþ ñòîðîíó äëÿ íàèëó÷øåãî ñîâìåùåíèÿ ñ äàííûìè â öåíòðå äèñêà. Òàêàÿ ïðîöåäóðà ïîçâîëèëà íàì ñðàâ íèòü îòíîøåíèå ñïåêòðîâ ëèìá/öåíòð ñ ñîîòâåòñòâóþùèìè äàííûìè ðàáîò [17,29]. Â öåëîì íàøè äàííûå õîðîøî ñîãëàñóþòñÿ ñ äàííûìè [29].…”

“…Ðàñõîaeäåíèå ïîëó÷åííûõ ðåçóëüòàòîâ âî ìíîãîì âûçâàíî ðàçëè÷èåì ñïåêòðàëüíîãî ðàçðåøåíèÿ èñïîëüçóåìûõ èíñòðóìåíòîâ è ðàçëè÷èåì àïåðòóð ïðè íàáëþäåíèÿõ íà ëèìáå. Êðîìå òîãî, íàáëþäàåìûå îòëè÷èÿ ìîãóò áûòü îáóñëîâëåíû è ôàêòîì íåîäíî âðåìåííîñòè ðåãèñòðàöèè ñïåêòðîâ â öåíòðå è íà ëèìáå Ñîëíöà â ðà áî òàõ [17,29].…”