The First X-Ray Polarization Observation of the Black Hole X-Ray Binary 4U 1630-47 in the Steep Power-law State
Date Issued
2023
Author(s)
Rodriguez Cavero, Nicole
•
•
Krawczynski, Henric
•
Dovčiak, Michal
•
Bianchi, Stefano
•
Steiner, James F.
•
Svoboda, Jiri
•
•
•
Negro, Michela
•
Ingram, Adam
•
Tennant, Allyn F.
•
Thomas, Nicholas E.
•
•
•
Tsygankov, Sergey S.
•
Turolla, Roberto
•
Vink, Jacco
•
Weisskopf, Martin C.
•
Wu, Kinwah
•
•
Veledina, Alexandra
•
Taverna, Roberto
•
Karas, Vladimir
•
•
Podgorný, Jakub
•
•
Suleimanov, Valery
•
•
Zane, Silvia
•
Kaaret, Philip
•
•
Poutanen, Juri
•
•
Petrucci, Pierre-Olivier
•
Gau, Ephraim
•
Hu, Kun
•
Chun, Sohee
•
Agudo, Iván
•
•
•
Baldini, Luca
•
Baumgartner, Wayne H.
•
Bellazzini, Ronaldo
•
Bongiorno, Stephen D.
•
Bonino, Raffaella
•
Brez, Alessandro
•
•
Castellano, Simone
•
Cavazzuti, Elisabetta
•
Chen, Chien-Ting
•
Ciprini, Stefano
•
•
•
•
Di Gesu, Laura
•
Di Lalla, Niccolò
•
•
Donnarumma, Immacolata
•
Doroshenko, Victor
•
Ehlert, Steven R.
•
Enoto, Teruaki
•
•
•
•
García, Javier A.
•
Gunji, Shuichi
•
Hayashida, Kiyoshi
•
Heyl, Jeremy
•
Iwakiri, Wataru
•
Jorstad, Svetlana G.
•
Kislat, Fabian
•
Kitaguchi, Takao
•
Kolodziejczak, Jeffery J.
•
•
Latronico, Luca
•
Liodakis, Ioannis
•
Maldera, Simone
•
Manfreda, Alberto
•
Marin, Frédéric
•
Marinucci, Andrea
•
Marscher, Alan P.
•
Marshall, Herman L.
•
•
Mitsuishi, Ikuyuki
•
Mizuno, Tsunefumi
•
Ng, Chi-Yung
•
O'Dell, Stephen L.
•
Omodei, Nicola
•
Oppedisano, Chiara
•
•
Pavlov, George G.
•
Peirson, Abel L.
•
•
Pesce-Rollins, Melissa
•
•
•
Puccetti, Simonetta
•
Ramsey, Brian D.
•
•
Roberts, Oliver J.
•
Romani, Roger W.
•
Sgrò, Carmelo
•
Slane, Patrick
•
Spandre, Gloria
•
•
Swartz, Douglas A.
•
Tamagawa, Toru
•
•
Tawara, Yuzuru
Abstract
The Imaging X-ray Polarimetry Explorer (IXPE) observed the black hole X-ray binary 4U 1630-47 in the steep power-law (or very high) state. The observations reveal a linear polarization degree of the 2-8 keV X-rays of 6.8% ± 0.2% at a position angle of 21.°3 ± 0.°9 east of north (all errors at 1σ confidence level). Whereas the polarization degree increases with energy, the polarization angle stays constant within the accuracy of our measurements. We compare the polarization of the source in the steep power-law state with the previous IXPE measurement of the source in the high soft state. We find that, even though the source flux and spectral shape are significantly different between the high soft state and the steep power-law state, their polarization signatures are similar. Assuming that the polarization of both the thermal and power-law emission components are constant over time, we estimate the power-law component polarization to be 6.8%-7.0% and note that the polarization angle of the thermal and power-law components must be approximately aligned. We discuss the implications for the origin of the power-law component and the properties of the emitting plasma.
Volume
958
Issue
1
Start page
L8
Issn Identifier
2041-8205
Ads BibCode
2023ApJ...958L...8R
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
Rodriguez_Cavero_2023_ApJL_958_L8.pdf
Description
PDF editoriale
Size
1.65 MB
Format
Adobe PDF
Checksum (MD5)
46189b80b1dbb58e4508a5280b480b30