papers

Publications (19)

astro-ph.HE2024

Tracking the X-ray Polarization of the Black Hole Transient Swift J1727.8-1613 during a State Transition

Adam Ingram, Niek Bollemeijer, Alexandra Veledina +120

We report on an observational campaign on the bright black hole X-ray binary Swift J1727.81613 centered around five observations by the Imaging X-ray Polarimetry Explorer (IXPE)…

astro-ph.HE2023

The High Energy X-ray Probe (HEX-P): Probing Accretion onto Stellar Mass Black Holes

Riley Connors, John Tomsick, Paul Draghis +20

Accretion is a universal astrophysical process that plays a key role in cosmic history, from the epoch of reionization to galaxy and stellar formation and evolution. Accreting stel…

astro-ph.HE2022

Revisiting the galactic X-ray binary MAXI J1631-479: Implications for high inclination and a massive black hole

Sandeep K. Rout, Santosh Vadawale, Javier Garcia +1

X-ray spectroscopy of galactic black hole binaries serve as a powerful tool to gain an overall understanding of the system. Not only can the properties of the accretion disk be stu…

astro-ph.HE2024

Characterizing the Broadband Reflection Spectrum of MAXI J1803-298 During its 2021 Outburst with NuSTAR and NICER

Oluwashina Adegoke, Javier Garcia, Riley Connors +12

MAXI J1803-298 is a transient black hole candidate discovered in May of 2021 during an outburst that lasted several months. Multiple X-ray observations reveal recurring "dipping" i…

astro-ph.HE2024

Proof of principle X-ray reflection mass measurement of the black hole in H1743-322

Edward Nathan, Adam Ingram, James F. Steiner +9

The black hole X-ray binary H1743-322 lies in a region of the Galaxy with high extinction, and therefore it has not been possible to make a dynamical mass measurement. In this pape…

astro-ph.HE2025

The very high X-ray polarisation of accreting black hole IGRJ17091-3624 in the hard state

Melissa Ewing, Maxime Parra, Guglielmo Mastroserio +26

We report the first detection of the X-ray polarisation of the transient black hole X-ray binary IGRJ17091-3624 taken with the Imaging X-ray polarimetry Explorer (IXPE) in March 20…

astro-ph.HE2017

A jet-dominated model for a broad-band spectral energy distribution of the nearby low-luminosity active galactic nucleus in M94

Pieter van Oers, Sera Markoff, Phil Uttley +4

We have compiled a new multiwavelength spectral energy distribution (SED) for the closest obscured low-ionization emission-line region active galactic nucleus (AGN), NGC 4736, also…

astro-ph.HE2024

Highly-coherent quasi-periodic oscillations in the 'heartbeat' black hole X-ray binary IGR J17091-3624

Jingyi Wang, Erin Kara, Jeroen Homan +13

IGR J17091-3624 is a black hole X-ray binary (BHXB), often referred to as the 'twin' of GRS 1915+105 because it is the only other known BHXB that can show exotic 'heartbeat'-like v…

astro-ph.HE2023

Variability as a predictor for the hard-to-soft state transition in GX 339-4

Matteo Lucchini, Marina Ten Have, Jingyi Wang +17

During the outbursts of black hole X-ray binaries (BHXRBs), their accretion flows transition through several states. The source luminosity rises in the hard state, dominated by non…

astro-ph.HE2021

Disk, Corona, Jet Connection in the Intermediate State of MAXI J1820+070 Revealed by NICER Spectral-Timing Analysis

Jingyi Wang, Guglielmo Mastroserio, Erin Kara +14

We analyze 5 epochs of NICER data of the black hole X-ray binary MAXI J1820+070 during the bright hard-to-soft state transition in its 2018 outburst with both reflection spectrosco…

astro-ph.HE2021

Modelling correlated variability in accreting black holes: the effect of high density and variable ionisation on reverberation lags

Guglielmo Mastroserio, Adam Ingram, Jingyi Wang +9

We present a new release of the RELTRANS model to fit the complex cross-spectrum of accreting black holes as a function of energy. The model accounts for continuum lags and reverbe…

astro-ph.HE2022

The NICER "Reverberation Machine": A Systematic Study of Time Lags in Black Hole X-Ray Binaries

Jingyi Wang, Erin Kara, Matteo Lucchini +12

We perform the first systematic search of all NICER archival observations of black hole (and candidate) low-mass X-ray binaries for signatures of reverberation. Reverberation lags…

astro-ph.HE2026

Black-Hole Spin Measurements from X-ray Reflection Spectroscopy: Quality Criteria and Community Recommendations

Javier A. Garcia, Riley Connors, Laura W. Brenneman +1

The paper proposes a practical framework and checklist for assessing the reliability of black‑hole spin measurements obtained via X‑ray reflection spectroscopy, defining criteria f…

#black hole spin#x-ray reflection spectroscopy#spectral modeling#data quality assessment
astro-ph.HE2024

The 2022 Outburst of IGR J17091-3624: Connecting the exotic GRS 1915+105 to standard black hole X-ray binaries

Jingyi Wang, Erin Kara, Javier A. García +13

While the standard X-ray variability of black hole X-ray binaries (BHXBs) is stochastic and noisy, there are two known BHXBs that exhibit exotic `heartbeat'-like variability in the…

astro-ph.HE2023

X-ray Reflection from the Plunging Region of Black Hole Accretion Disks

Jameson Dong, Guglielmo Mastroserio, Javier A. Garcıa +3

Accretion around black holes is very often characterized by distinctive X-ray reflection features (mostly, iron inner-shell transitions), which arise due to the primary radiation b…

astro-ph.HE2024

Modeling Multiple X-Ray Reflection in Super-Eddington Winds

Zijian Zhang, Lars Lund Thomsen, Lixin Dai +7

It has been recently discovered that a few super-Eddington sources undergoing black hole super-Eddington accretion exhibit X-ray reflection signatures. In such new systems, one exp…

astro-ph.HE2021

Reflection Modeling of the Black Hole Binary 4U~163047: the Disk Density and Returning Radiation

Riley Connors, Javier García, John Tomsick +11

We present the analysis of X-ray observations of the black hole binary 4U~163047 using relativistic reflection spectroscopy. We use archival data from the RXTE, Swift, and NuSTA…

astro-ph.HE2020

Multi-wavelength detectability of isolated black holes in the Milky Way

Francesca Scarcella, Daniele Gaggero, Riley Connors +3

Isolated black holes in our Galaxy have eluded detection so far. We present here a comprehensive study on the detectability of isolated stellar-mass astrophysical black holes that…

astro-ph.HE2021

On measuring the Hubble constant with X-ray reverberation mapping of active galactic nuclei

Adam Ingram, Guglielmo Mastroserio, Michiel van der Klis +8

We show that X-ray reverberation mapping can be used to measure the distance to type 1 active galactic nuclei (AGNs). This is because X-ray photons originally emitted from the `cor…