Publications (36)
The Dynamic X-ray Sky of the Local Universe
Alicia M. Soderberg, Jonathan E. Grindlay, Joshua S. Bloom +35
Over the next decade, we can expect time domain astronomy to flourish at optical and radio wavelengths. In parallel with these efforts, a dedicated transient "machine" operating at…
TeV J2032+4130: a not-so-dark Accelerator?
Yousaf M. Butt, Jorge A. Combi, Jeremy Drake +5
The HEGRA gamma-ray source TeV J2032+4130 is considered the prototypical 'dark accelerator', since it was the first TeV source detected with no firm counterparts at lower frequenci…
Shocks in the outflow of the RS Oph 2021 eruption observed with X-ray gratings
Marina Orio, Ehud Behar, Juan Luna +9
The 2021 outburst of the symbiotic recurrent nova RS Oph was observed with the Chandra High Energy Transmission Gratings (HETG) on day 18 after optical maximum and with XMM-Newton…
Spectropolarimetry for Discerning Geometry and Structure in Circumstellar Media of Hot Massive Stars
Richard Ignace, Kenneth Gayley, Roberto Casini +3
Spectropolarimetric techniques are a mainstay of astrophysical inquiry, ranging from Solar System objects to the Cosmic Background Radiation. This review highlights applications of…
Spectroscopic follow-up of UV-excess objects selected from the UVEX survey
Kars Verbeek, Paul J. Groot, Simone Scaringi +17
We present the results of the first spectroscopic follow-up of 132 optically blue UV-excess sources selected from the UV-excess survey of the Northern Galactic Plane (UVEX). The UV…
Deeper Chandra Follow-up of Cygnus TeV Source Perpetuates Mystery
Yousaf Butt, Jeremy Drake, Paula Benaglia +4
A 50 ksec Chandra observation of the unidentified TeV source in Cygnus reported by the HEGRA collaboration reveals no obvious diffuse X-ray counterpart. However, 240 Pointlike X-ra…
IPHAS discoveries of young stars towards Cyg OB2 and its southern periphery
Jorick S. Vink, Janet E. Drew, Danny Steeghs +5
We report on the discovery of over 50 strong Halpha emitting objects towards the large OB association Cyg OB2 and the HII region DR 15 on its southern periphery. This was achieved…
Bayesian Spectral Analysis of Metal Abandance Deficient Stars
Epaminondas Sourlas, David van Dyk, Vinay Kashyap +2
Metallicity can be measured by analyzing the spectra in the X-ray region and comparing the flux in spectral lines to the flux in the underlying Bremsstrahlung continuum. In this pa…
Exploring the Small Magellanic Cloud to the Faintest X-ray Fluxes: Source Catalog, Timing and Spectral Analysis
Silas Laycock, Andreas Zezas, Jaesub Hong +2
We present the results of a pair of 100 ksec Chandra observations in the Small Magellanic Cloud to survey high mass X-ray binaries (HMXBs), stars and LMXBs/CVs down to Lx = 4.3 x 1…
Flare Heating in Stellar Coronae
Vinay Kashyap, Jeremy Drake, Manuel Guedel +1
We investigate the contribution of very weak flares to the coronal luminosity of low-mass active stars. We analyze EUVE/DS events data from FK Aqr, V1054 Oph, and AD Leo and conclu…
Stellar Activity and Coronal Heating: an overview of recent results
Paola Testa, Steve Saar, Jeremy Drake
Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes lea…
Exoplanet Modulation of Stellar Coronal Radio Emission
Ofer Cohen, Sofia-Paraskevi Moschou, Alex Glocer +5
The search for exoplanets in the radio bands has been focused on detecting radio emissions produced by the interaction between magnetized planets and the stellar wind (auroral emis…
Eclipse Mapping of EXO 0748-676: Evidence for a Massive Neutron Star
Amy H. Knight, Adam Ingram, Matthew Middleton +1
Determining the maximum possible neutron star (NS) mass places limits on the equation of state (EoS) of ultra-dense matter. The mass of NSs in low mass X-ray binaries can be determ…
Structure and Evolution of Pre-Main Sequence Stars
Norbert S. Schulz, Glenn Allen, Mark W. Bautz +28
Low-mass pre-main sequence (PMS) stars are strong and variable X-ray emitters, as has been well established by EINSTEIN and ROSAT observatories. It was originally believed that thi…
Line Emission Mapper (LEM): Probing the physics of cosmic ecosystems
Ralph Kraft, Maxim Markevitch, Caroline Kilbourne +107
The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative…
STROBE-X: X-ray Timing and Spectroscopy on Dynamical Timescales from Microseconds to Years
Paul S. Ray, Zaven Arzoumanian, David Ballantyne +155
We present the Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X), a probe-class mission concept selected for study by NASA. It combines huge collectin…
Deep Chandra Survey of the Small Magellanic Cloud. II. Timing Analysis of X-ray Pulsars
JaeSub Hong, Vallia Antoniou, Andreas Zezas +5
We report the timing analysis results of X-ray pulsars from a recent deep Chandra survey of the Small Magellanic Cloud (SMC). We have analyzed a total exposure of 1.4 Ms from 31 ob…
Stars at High Spatial Resolution
Kenneth G. Carpenter, Gerard van Belle, Alexander Brown +19
We summarize some of the compelling new scientific opportunities for understanding stars and stellar systems that can be enabled by sub-milliarcsec (sub-mas) angular resolution, UV…
Enabling New ALMA Science with Improved Support for Time-Domain Observations
Kate D. Alexander, Edo Berger, Geoff Bower +34
While the Atacama Large Millimeter/submillimeter Array (ALMA) is a uniquely powerful telescope, its impact in certain fields of astrophysics has been limited by observatory policie…
CHANDRA/VLA Follow-up of TeV J2032+4131, the Only Unidentified TeV Gamma-ray Source
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The HEGRA Cherenkov telescope array group recently reported a steady and extended unidentified TeV gamma-ray source lying at the outskirts of Cygnus OB2. This is the most massive s…
Astro2020 Science White Paper: Understanding the evolution of close white dwarf binaries
Odette Toloza, Elme Breed, Domitilla De Martino +27
Interacting binaries containing white dwarfs can lead to a variety of outcomes that range from powerful thermonuclear explosions, which are important in the chemical evolution of g…
Addressing Decadal Survey Science through Community Access to Highly Multiplexed Spectroscopy with BigBOSS on the KPNO Mayall Telescope
Caty Pilachowski, Carles Badenes, Stephen Bailey +87
This document summarizes the results of a community-based discussion of the potential science impact of the Mayall+BigBOSS highly multiplexed multi-object spectroscopic capability.…
On X-ray Variability in Active Binary Stars
Vinay Kashyap, Jeremy Drake
We compare the count-rates of active binaries observed by Einstein and ROSAT. We find significant evidence for short-term variability (approx 0.32) and marginal evidence for a larg…
Chandra Detection of the First X-ray Forest along the Line of Sight To Mkn 421
Fabrizio Nicastro, Smita Mathur, Martin Elvis +7
We present the first >=3.5 sigma (conservative) or >=5.8 sigma (sum of lines significance) detection of two Warm-Hot Intergalactic Medium (WHIM) filaments at z>0, which we find alo…
Cosmic Ray Acceleration by Stellar Associations? The Case of Cygnus OB2
Yousaf Butt, Paula Benaglia, Jorge Combi +10
The origins of all extra-solar cosmic rays -- both the ultra high-energy and lower energy Galactic variety -- remain unclear. It has been argued that the large scale shocks and tur…
The aftermath of nova Cen 2013 (V1369 Cen)
Elena Mason, Steven N. Shore, Jeremy Drake +3
Context: Classical nova progenitors are cataclysmic variables and very old novae are observed to match high mass transfer rate and (relatively) long orbital period systems. However…
X-ray Studies of Planetary Systems: An Astro2010 Decadal Survey White Paper
Eric Feigelson, Jeremy Drake, Ronald Elsner +7
While it may seem counterintuitive that X-ray astronomy should give any insights into low-temperature planetary systems, planets orbit stars whose magnetized surfaces divert a smal…
The Early Evolution of Stars and Exoplanet Systems: Exploring and Exploiting Nearby, Young Stars (an Astro2020 Science White Paper)
Joel H. Kastner, Katelyn Allers, Brendan Bowler +12
Our knowledge of the population of young (age <=750 Myr) stars that lie within ~120 pc of the Sun is rapidly accelerating. The vast majority of these nearby, young stars can be pla…
Heating of the Atmospheres of Short-orbit Exoplanets by Their Rapid Orbital Motion Through an Extreme Space Environment
Ofer Cohen, Alex Glocer, Cecilia Garraffo +4
Exoplanets with short orbit period reside very close to their host stars. They transition very rapidly between different sectors of the circumstellar space environment along their…
X-ray Observations of Nova Scorpii 2023 (V1716 Sco) in Outburst
John Worley, Marina Orio, Andrej Dobrotka +5
Nova Scorpii 2023 was first detected as a luminous supersoft X-ray source (SSS) 93 days after outburst and continued emitting soft X-rays for over two months, until it was too clos…
Chandra Multi-wavelength Plane (ChaMPlane) Survey: Design and Initial Results
Jonathan Grindlay, Ping Zhao, JaeSub Hong +9
The Chandra Multiwavength Plane (ChaMPlane) Survey of the galactic plane incorporates serendipitous sources from selected Chandra pointings in or near the galactic plane (b < 12deg…
The Hot and Energetic Universe: A White Paper presenting the science theme motivating the Athena+ mission
Kirpal Nandra, Didier Barret, Xavier Barcons +237
This White Paper, submitted to the recent ESA call for science themes to define its future large missions, advocates the need for a transformational leap in our understanding of tw…
Three-dimensional, Time-dependent MHD Simulation of Disk-Magnetosphere-Stellar Wind Interaction in a T Tauri, Protoplanetary System
Ofer Cohen, Cecilia Garraffo, Jeremy Drake +4
We present a three-dimensional, time-dependent, MHD simulation of the short-term interaction between a protoplanetary disk and the stellar corona in a T Tauri system. The simulatio…
EUV influences on exoplanet atmospheric stability and evolution
Allison Youngblood, Kevin France, Tommi Koskinen +15
The planetary effective surface temperature alone is insufficient to characterize exoplanet atmospheres and their stability or evolution. Considering the star-planet system as a wh…
Understanding Galactic Star Formation with Next Generation X-ray Spectroscopy and Imaging
Scott J. Wolk, Rachel Osten, Nancy Brickhouse +8
This white paper is motivated by open questions in star formation, which can be uniquely addressed by high resolution X-ray imaging and require an X-ray observatory with large coll…
EUV observations of cool dwarf stars
Allison Youngblood, Jeremy Drake, James Mason +15
The EUV (100-912 Ã ) is a spectral region notoriously difficult to observe due to attenuation by neutral hydrogen gas in the interstellar medium. Despite this, hundreds to thousand…