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Summary WD/iNS Working Group IACHEC #11, Pune, India
Jeremy Drake K.P. Singh Vinay Kashyap Prof. Li Ming Shijie Zheng
Dipankar BaJarachaya Shabnam Iyyani Firosa Sutaria Vadim Burwitz
2016-‐02-‐29
AJendees:
ObservaYons with ASTROSAT • Instrument Contraints – SXT • FoV 40‘ diameter (jiJer ~6‘) • PSF 2‘-‐4‘ diameter (with JiJer)
– UVIT • FoV 28‘ diameter (40‘ with drid and JiJer) • no bright sources in <20‘ radius
WD ObservaYons with ASTROSAT • HZ43A (HZ43B M3.5 star 13mag, check if flaring) – SXT (observed, check high energy cut-‐off) – UVIT (check if observable)
• GD153 – SXT (observed but undetected à too faint) – UVIT (check if observable, check if graYng possible)
• Models – Physical models
• Rauch, Barstow (Hubeny) NLTE Models • Best Fits
– Papers Beuermann; Paper Kaastrarake – Thesis Menz
• HST – absolute flux calibraYon
iNS ObservaYons with ASTROSAT • RXJ1856 – SXT (not observed yet important for low E calibraYon) – UVIT (opYcally very faint: 26 mag in HAST)
• Models – Blackbody (well contrained from exisYng missions)
• Sufficient for calibraYng response shape • RelaYve calibraYon
– Physical models • Different approaches : strongly magneYzed atmospheres à same shape as bb model
WG AcYons • Provide KP with Rauch models for fipng ASAP (March 2016), as tables
for XSPEC ✔���à see 1st fit to ASTROSAT HZ43A data on subsequent pages
• SXT definitely requires RXJ1856 observaYon à to help improve the low energy response
• iNS provide blackbody model parameters from Drake and Burwitz papers + IACHEC efforts
• Add Models and LETGS spectra to IACHEC wiki
• Check HZ43A and HZ43B co-‐added spectra for high energy tail in HRC-‐S + LETG (Vinay, Jeremy)
• HITOMI à
WD model values from combined Chandra LETGS
Rauch NLTE 7.9 51.25 1.4 (free) 0.0
ASTROSAT SXT
Menz 2011 Note: there is a factor of 3 difference between the Rauch and literature normalizaYon constants
0.510−3
0.01
0.1
1
norm
aliz
ed c
ount
s s−
1 keV
−1
Energy (keV)
HZ43 14050s SXT exposure
kps 2−Mar−2016 08:09
HZ43A ASTROSAT SXT 14ksec: Overview
Background level to be determined more precisely
HZ43A ASTROSAT SXT 14ksec Detail
0.22 0.30 0.34
Using default SXT • ARF (simulated) • RMF (ground calibraYon) Model • Thomas Rauch NLTE • Parameters from fit
• RMF needs checking at this low energy range àonly calibrated down to 0.3keV on ground • Background subtracYon not yet ideal to be checked
Rauch NLTE model Log g = 7.9 T = 51.250 KK norm = 1.4 (free) LETGS norm ~ 1.0
WG AcYons • Provide KP with Rauch models for fipng ASAP (March 2016), as tables
for XSPEC ✔���à see 1st fit to ASTROSAT HZ43A data on subsequent pages
• SXT definitely requires RXJ1856 observaYon à to help improve the low energy response
• iNS provide blackbody model parameters from Drake and Burwitz papers + IACHEC efforts
• Add Models and LETGS spectra to IACHEC wiki
• Check HZ43A and HZ43B co-‐added spectra for high energy tail in HRC-‐S + LETG (Vinay, Jeremy)
• HITOMI à