Zobrazeno 1 - 10
of 250
pro vyhledávání: '"Grupe, Dirk"'
Autor:
Green, Kaylie S., Gallagher, Sarah C., Leighly, Karen M., Choi, Hyunseop, Grupe, Dirk, Terndrup, Donald M., Richards, Gordon T., Komossa, S.
Publikováno v:
2023, ApJ, 953, 186
Broad Absorption Line Quasars (BALQs) are actively accreting supermassive black holes that have strong outflows characterized by broad absorption lines in their rest-UV spectra. Variability in these absorption lines occurs over months to years depend
Externí odkaz:
http://arxiv.org/abs/2405.06027
We report on follow-up observations of the Seyfert 1.9 galaxy IC 3599 with the NASA Neil Gehrels Swift mission. The detection of a second X-ray outburst in 2010 by Swift after the first discovery of a bright X-ray outburst in 1990 by ROSAT led to the
Externí odkaz:
http://arxiv.org/abs/2404.19107
Autor:
Green, Matthew J., Hermes, J. J., Barlow, Brad N., Marsh, T. R., Pelisoli, Ingrid, Gänsicke, Boris T., Kaiser, Ben C., Romero, Alejandra, Amaral, Larissa Antunes, Corcoran, Kyle, Grupe, Dirk, Kennedy, Mark R., Kepler, S. O., Munday, James, Ashley, R. P., Baran, Andrzej S., Breedt, Elmé, Brown, Alex J., Dhillon, V. S., Dyer, Martin J., Kerry, Paul, King, George W., Littlefair, S. P., Parsons, Steven G., Sahman, David I.
AM CVn-type systems are ultracompact, helium-accreting binary systems which are evolutionarily linked to the progenitors of thermonuclear supernovae and are expected to be strong Galactic sources of gravitational waves detectable to upcoming space-ba
Externí odkaz:
http://arxiv.org/abs/2311.01255
Autor:
Hu, Zhensong, Su, Yuanyuan, Li, Zhiyuan, Hess, Kelley M., Kraft, Ralph P., Forman, William R., Nulsen, Paul E. J., Sridhar, Sarrvesh S., Stroe, Andra, Baek, Junhyun, Chung, Aeree, Grupe, Dirk, Chen, Hao, Irwin, Jimmy A., Jones, Christine, Randall, Scott W., Roediger, Elke
To understand the formation and growth of supermassive black holes (SMBHs) and their co-evolution with host galaxies, it is essential to know the impact of environment on the activity of active galactic nuclei (AGN). We present new Chandra X-ray obse
Externí odkaz:
http://arxiv.org/abs/2308.12565
Autor:
Yu, Zhibo, Jiang, Jiachen, Bambi, Cosimo, Gallo, Luigi C., Grupe, Dirk, Fabian, Andrew C., Reynolds, Christopher S., Brandt, William N.
Publikováno v:
Monthly Notices of the Royal Astronomical Society, Volume 522, Issue 4, July 2023, Pages 5456-5468
We report a detailed analysis of the XMM-Newton spectra of six Narrow-Line Seyfert 1 (NLS1) galaxies at redshift z = 0.35--0.92. Compared with the NLS1s at lower redshift in the previously most-studied sample, these NLS1s have larger black hole (BH)
Externí odkaz:
http://arxiv.org/abs/2305.00991
Autor:
Kara, Erin, Barth, Aaron J., Cackett, Edward M., Gelbord, Jonathan, Montano, John, Li, Yan-Rong, Santana, Lisabeth, Horne, Keith, Alston, William N., Buisson, Douglas, Chelouche, Doron, Du, Pu, Fabian, Andrew C., Fian, Carina, Gallo, Luigi, Goad, Michael R., Grupe, Dirk, Buitrago, Diego H. Gonzalez, Santisteban, Juan V. Hernandez, Kaspi, Shai, Hu, Chen, Komossa, S., Kriss, Gerard A., Lewin, Collin, Lewis, Tiffany, Loewenstein, Michael, Lohfink, Anne, Masterson, Megan, McHardy, Ian M., Mehdipour, Missagh, Miller, Jake, Panagiotou, Christos, Parker, Michael L., Pinto, Ciro, Remillard, Ron, Reynolds, Christopher, Rogantini, Daniele, Wang, Jian-Min, Wang, Jingyi, Wilkins, Dan
We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an unprecedented low X-ray flux state. Despite dramatic suppression of the
Externí odkaz:
http://arxiv.org/abs/2302.07342
Autor:
Kollatschny, Wolfram, Grupe, Dirk, Parker, Michael L., Ochmann, Martin W., Schartel, Norbert, Romero-Colmenero, Encarni, Winkler, Hartmut, Komossa, Stefanie, Famula, Philipp, Probst, Malte A., Santos-Lleo, Maria
Publikováno v:
A&A 670, A103 (2023)
IRAS23226-3843 has previously been classified as a changing-look AGN based on X-ray and optical spectral variations. In 2019, Swift observations revealed a strong rebrightening in X-ray and UV fluxes in comparison to observations in 2017. We took fol
Externí odkaz:
http://arxiv.org/abs/2212.07270
Autor:
Lawther, Daniel, Vestergaard, Marianne, Raimundo, Sandra, Koay, Jun Yi, Peterson, Bradley M, Fan, Xiaohui, Grupe, Dirk, Mathur, Smita
Mrk 590 is a known changing-look AGN which almost turned off in 2012, and then in 2017 partially re-ignited into a repeat flaring state, unusual for an AGN. Our \emph{Swift} observations since 2013 allow us to characterise the accretion-generated emi
Externí odkaz:
http://arxiv.org/abs/2211.14371
Autor:
Valtonen, Mauri J., Zola, Staszek, Gopakumar, A., McCall, Callum, Jermak, Helen, Dey, Lankeswar, Komossa, S., Pursimo, Tapio, Knudstrup, Emil, Grupe, Dirk, Gomez, Jose L., Hudec, Rene, Jelinek, Martin, Strobl, Jan, Berdyugin, Andrei V., Ciprini, Stefano, Reichart, Daniel E., Kouprianov, Vladimir V., Matsumoto, Katsura, Drozdz, Marek, Mugrauer, Markus, Sadun, Alberto, Zejmo, Michal, Sillanpaa, Aimo, Lehto, Harry J., Nilsson, Kari
The bright blazar OJ~287 routinely parades high brightness bremsstrahlung flares which are explained as being a result of a secondary supermassive black hole (SMBH) impacting the accretion disk of a primary SMBH in a binary system. We begin by showin
Externí odkaz:
http://arxiv.org/abs/2209.08360