Craig Heinke | University of Alberta (original) (raw)

Papers by Craig Heinke

Research paper thumbnail of Combining Electromagnetic and Gravitational-Wave Constraints on Neutron-Star Masses and Radii

Research paper thumbnail of The MAVERIC Survey: New Compact Binaries Revealed by Deep Radio Continuum Observations of the Galactic Globular Cluster Terzan 5

The Astrophysical Journal

Research paper thumbnail of Chandra Spectral and Timing Analysis of Sgr A*'s Brightest X-Ray Flares

The Astrophysical Journal

Research paper thumbnail of The X-ray emissivity of low-density stellar populations

Monthly Notices of the Royal Astronomical Society

The dynamical production of low-mass X-ray binaries and brighter cataclysmic variables (CVs) in d... more The dynamical production of low-mass X-ray binaries and brighter cataclysmic variables (CVs) in dense globular clusters is well-established. We investigate how the X-ray emissivity of fainter X-ray binaries (principally CVs and coronally active binaries) varies between different environments. We compile calculations (largely from the literature) of the X-ray emissivity of old stellar populations, including open and globular clusters and several galaxies. We investigate three literature claims of unusual X-ray sources in low-density stellar populations. We show that a suggested quiescent neutron star in the open cluster NGC 6819 is a foreground M dwarf. We show that the suggested diffuse X-ray emission from an old nova shell in the globular cluster NGC 6366 is actually a background galaxy cluster. And we show that a suggested population of quiescent X-ray binaries in the Sculptor Dwarf Galaxy is mostly (perhaps entirely) background galaxies. We find that above densities of 104 M⊙ pc−...

Research paper thumbnail of A Serendipitous Pulsar Discovery in a Search for a Companion to a Low-mass White Dwarf

Research Notes of the AAS

Research paper thumbnail of A Deep X-ray Survey of the globular cluster Omega Centauri

Monthly Notices of the Royal Astronomical Society

Research paper thumbnail of The Hottest Superfluid and Superconductor in the Universe: Discovery and Nuclear Physics Implications

Proceedings of Xth Quark Confinement and the Hadron Spectrum — PoS(Confinement X)

Research paper thumbnail of Constraining the mass and radius of neutron stars in globular clusters

Monthly Notices of the Royal Astronomical Society

Research paper thumbnail of Low mass X-ray binaries in the Inner Galaxy: implications for millisecond pulsars and the GeV excess

Journal of Cosmology and Astroparticle Physics

Research paper thumbnail of Neutron Star Mass–Radius Constraints of the Quiescent Low-Mass X-Ray Binaries X7 and X5 in the Globular Cluster 47 Tuc

The Astrophysical Journal, 2016

Research paper thumbnail of Understanding dim globular cluster X-ray sources

I investigate the dim (L X < 10 35 ergs s -1 ) X-ray sources in galactic globular clusters, co... more I investigate the dim (L X < 10 35 ergs s -1 ) X-ray sources in galactic globular clusters, constraining their nature and properties with Chandra X-ray observations. Three faint X-ray sources are identified in a short Chandra observation of the globular cluster NGC 6652, in addition to a known ...

Research paper thumbnail of Revealing a new symbiotic X-ray binary with Gemini NIFS

Monthly Notices of the Royal Astronomical Society, Mar 27, 2014

We use K-band spectroscopy of the counterpart to the rapidly variable X-ray transient XMMU J17444... more We use K-band spectroscopy of the counterpart to the rapidly variable X-ray transient XMMU J174445.5-295044 to identify it as a new symbiotic X-ray binary. XMMU J174445.5-295044 has shown a hard X-ray spectrum (we verify its association with an Integral/IBIS 18-40 keV detection in 2013 using a short Swift/XRT observation), high and varying N$_H$, and rapid flares on timescales down to minutes, suggesting wind accretion onto a compact star. We observed its near-infrared counterpart using the Near-infrared Integral Field Spectrograph (NIFS) at Gemini-North, and classify the companion as ~ M2 III. We infer a distance of 3.1+1.8−1.13.1^{+1.8}_{-1.1}3.1+1.8−1.1 kpc (conservative 1-sigma errors), and therefore calculate that the observed X-ray luminosity (2-10 keV) has reached to at least 4$\times10^{34}$ erg/s. We therefore conclude that the source is a symbiotic X-ray binary containing a neutron star (or, less likely, black hole) accreting from the wind of a giant.

Research paper thumbnail of Swift imaging shows no evidence for active AGN near Crab

The detection of enhanced gamma-ray (>100 MeV) flux from the direction of the Crab Nebula by A... more The detection of enhanced gamma-ray (>100 MeV) flux from the direction of the Crab Nebula by AGILE (ATEL #2855) and Fermi (ATEL #2861) raises the question of whether the gamma-rays are from the Crab itself, or from a previously unknown gamma-ray source, such as an AGN, in close proximity to the Crab (the Fermi 1-sigma error radius is 3.6'). Although no changes have been noted in the overall X-ray flux from the Crab's direction (ATEL #2856, ATEL #2858), it is possible that a fainter X-ray source could have appeared, motivating imaging observations.

Research paper thumbnail of Stellar Metallicity Enhancement by Exoplanet Consumption

Recent studies have established a correlation between stars with extrasolar planets and enhanced ... more Recent studies have established a correlation between stars with extrasolar planets and enhanced observed metallicity as compared with the general population. One explanation for the enhancement, suggested by the close orbits of the planets so far discovered, is the pollution of convection zones of host stars by the infall of planetary material. The process of planet destruction in the outer

Research paper thumbnail of Identification of the LMXB and Faint X-ray Sources in NGC 6652

We have detected three new x-ray point sources, in addition to the known low-mass x-ray binary (L... more We have detected three new x-ray point sources, in addition to the known low-mass x-ray binary (LMXB) X1832-330, in the globular cluster NGC 6652 with a Chandra 1.6 ksec HRC-I exposure. Star 49 (M_{V}~4.7), suggested by Deutsch et al.(1998) as the optical candidate for the LMXB, is identified (<0.3") not with the LMXB, but with another, newly detected source (B). Using archival HST images, we identify (<0.3") the LMXB (A) and one of the remaining new sources (C) with blue variable optical counterparts at M_{V}~3.7 and 5.3 respectively. The other new source (D) remains unidentified in the crowded cluster core. In the 0.5-2.5 keV range, assuming a 5 keV thermal bremsstrahlung spectrum and N_{H}=5.5*10^{20}, source A has intrinsic luminosity L_{X}~5.3*10^{35} ergs/s. Assuming a 1 keV thermal bremsstrahlung spectrum, B has L_{X}~4.1*10^{33} ergs/s, while C and D have L_{X}~8*10^{32}$ ergs/s. Source B is probably a quiescent LMXB, while source C may be either a luminous CV or quiescent LMXB.

Research paper thumbnail of The Dense Matter Equation of State from Neutron Star Radius and Mass Measurements

The Astrophysical Journal, 2016

Research paper thumbnail of X-ray and Optical Studies of SAX J1808.4-3658 in Quiescence

AIP Conference Proceedings, 2008

ABSTRACT

Research paper thumbnail of Hubble Space Telescope Advanced Camera for Surveys Imaging of ω Centauri: Optical Counterpart for the Quiescent Low‐Mass X‐Ray Binary

The Astrophysical Journal, Sep 20, 2004

We report the discovery of an optical counterpart to a quiescent neutron star in the globular clu... more We report the discovery of an optical counterpart to a quiescent neutron star in the globular cluster omega Centauri (NGC 5139). The star was found as part of our wide-field imaging study of omega Cen using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. Its magnitude and color (R625=25.2, B435-R625=1.5) place it more than 1.5 mag to

Research paper thumbnail of Cataclysmic Variables in Globular Clusters, the Galactic Center, and Local Space

AIP Conference Proceedings, 2008

Research paper thumbnail of Chandra localisation of IGR J17361-4441 in the globular cluster NGC 6388

The Astronomer S Telegram, Sep 1, 2011

We report on a 2.5 ks Chandra observation of IGR J17361-4441 (ATel #3565, #3566, #3595, #3617) th... more We report on a 2.5 ks Chandra observation of IGR J17361-4441 (ATel #3565, #3566, #3595, #3617) that began on 2011-08-29 at 12:53 UT. The observation was taken with the ACIS S3 chip in half-chip subarray imaging mode. We use the CIAO tool wavdetect on a 0.5-6 keV image to determine the locations of the transient and several other sources in

Research paper thumbnail of Combining Electromagnetic and Gravitational-Wave Constraints on Neutron-Star Masses and Radii

Research paper thumbnail of The MAVERIC Survey: New Compact Binaries Revealed by Deep Radio Continuum Observations of the Galactic Globular Cluster Terzan 5

The Astrophysical Journal

Research paper thumbnail of Chandra Spectral and Timing Analysis of Sgr A*'s Brightest X-Ray Flares

The Astrophysical Journal

Research paper thumbnail of The X-ray emissivity of low-density stellar populations

Monthly Notices of the Royal Astronomical Society

The dynamical production of low-mass X-ray binaries and brighter cataclysmic variables (CVs) in d... more The dynamical production of low-mass X-ray binaries and brighter cataclysmic variables (CVs) in dense globular clusters is well-established. We investigate how the X-ray emissivity of fainter X-ray binaries (principally CVs and coronally active binaries) varies between different environments. We compile calculations (largely from the literature) of the X-ray emissivity of old stellar populations, including open and globular clusters and several galaxies. We investigate three literature claims of unusual X-ray sources in low-density stellar populations. We show that a suggested quiescent neutron star in the open cluster NGC 6819 is a foreground M dwarf. We show that the suggested diffuse X-ray emission from an old nova shell in the globular cluster NGC 6366 is actually a background galaxy cluster. And we show that a suggested population of quiescent X-ray binaries in the Sculptor Dwarf Galaxy is mostly (perhaps entirely) background galaxies. We find that above densities of 104 M⊙ pc−...

Research paper thumbnail of A Serendipitous Pulsar Discovery in a Search for a Companion to a Low-mass White Dwarf

Research Notes of the AAS

Research paper thumbnail of A Deep X-ray Survey of the globular cluster Omega Centauri

Monthly Notices of the Royal Astronomical Society

Research paper thumbnail of The Hottest Superfluid and Superconductor in the Universe: Discovery and Nuclear Physics Implications

Proceedings of Xth Quark Confinement and the Hadron Spectrum — PoS(Confinement X)

Research paper thumbnail of Constraining the mass and radius of neutron stars in globular clusters

Monthly Notices of the Royal Astronomical Society

Research paper thumbnail of Low mass X-ray binaries in the Inner Galaxy: implications for millisecond pulsars and the GeV excess

Journal of Cosmology and Astroparticle Physics

Research paper thumbnail of Neutron Star Mass–Radius Constraints of the Quiescent Low-Mass X-Ray Binaries X7 and X5 in the Globular Cluster 47 Tuc

The Astrophysical Journal, 2016

Research paper thumbnail of Understanding dim globular cluster X-ray sources

I investigate the dim (L X < 10 35 ergs s -1 ) X-ray sources in galactic globular clusters, co... more I investigate the dim (L X < 10 35 ergs s -1 ) X-ray sources in galactic globular clusters, constraining their nature and properties with Chandra X-ray observations. Three faint X-ray sources are identified in a short Chandra observation of the globular cluster NGC 6652, in addition to a known ...

Research paper thumbnail of Revealing a new symbiotic X-ray binary with Gemini NIFS

Monthly Notices of the Royal Astronomical Society, Mar 27, 2014

We use K-band spectroscopy of the counterpart to the rapidly variable X-ray transient XMMU J17444... more We use K-band spectroscopy of the counterpart to the rapidly variable X-ray transient XMMU J174445.5-295044 to identify it as a new symbiotic X-ray binary. XMMU J174445.5-295044 has shown a hard X-ray spectrum (we verify its association with an Integral/IBIS 18-40 keV detection in 2013 using a short Swift/XRT observation), high and varying N$_H$, and rapid flares on timescales down to minutes, suggesting wind accretion onto a compact star. We observed its near-infrared counterpart using the Near-infrared Integral Field Spectrograph (NIFS) at Gemini-North, and classify the companion as ~ M2 III. We infer a distance of 3.1+1.8−1.13.1^{+1.8}_{-1.1}3.1+1.8−1.1 kpc (conservative 1-sigma errors), and therefore calculate that the observed X-ray luminosity (2-10 keV) has reached to at least 4$\times10^{34}$ erg/s. We therefore conclude that the source is a symbiotic X-ray binary containing a neutron star (or, less likely, black hole) accreting from the wind of a giant.

Research paper thumbnail of Swift imaging shows no evidence for active AGN near Crab

The detection of enhanced gamma-ray (>100 MeV) flux from the direction of the Crab Nebula by A... more The detection of enhanced gamma-ray (>100 MeV) flux from the direction of the Crab Nebula by AGILE (ATEL #2855) and Fermi (ATEL #2861) raises the question of whether the gamma-rays are from the Crab itself, or from a previously unknown gamma-ray source, such as an AGN, in close proximity to the Crab (the Fermi 1-sigma error radius is 3.6'). Although no changes have been noted in the overall X-ray flux from the Crab's direction (ATEL #2856, ATEL #2858), it is possible that a fainter X-ray source could have appeared, motivating imaging observations.

Research paper thumbnail of Stellar Metallicity Enhancement by Exoplanet Consumption

Recent studies have established a correlation between stars with extrasolar planets and enhanced ... more Recent studies have established a correlation between stars with extrasolar planets and enhanced observed metallicity as compared with the general population. One explanation for the enhancement, suggested by the close orbits of the planets so far discovered, is the pollution of convection zones of host stars by the infall of planetary material. The process of planet destruction in the outer

Research paper thumbnail of Identification of the LMXB and Faint X-ray Sources in NGC 6652

We have detected three new x-ray point sources, in addition to the known low-mass x-ray binary (L... more We have detected three new x-ray point sources, in addition to the known low-mass x-ray binary (LMXB) X1832-330, in the globular cluster NGC 6652 with a Chandra 1.6 ksec HRC-I exposure. Star 49 (M_{V}~4.7), suggested by Deutsch et al.(1998) as the optical candidate for the LMXB, is identified (<0.3") not with the LMXB, but with another, newly detected source (B). Using archival HST images, we identify (<0.3") the LMXB (A) and one of the remaining new sources (C) with blue variable optical counterparts at M_{V}~3.7 and 5.3 respectively. The other new source (D) remains unidentified in the crowded cluster core. In the 0.5-2.5 keV range, assuming a 5 keV thermal bremsstrahlung spectrum and N_{H}=5.5*10^{20}, source A has intrinsic luminosity L_{X}~5.3*10^{35} ergs/s. Assuming a 1 keV thermal bremsstrahlung spectrum, B has L_{X}~4.1*10^{33} ergs/s, while C and D have L_{X}~8*10^{32}$ ergs/s. Source B is probably a quiescent LMXB, while source C may be either a luminous CV or quiescent LMXB.

Research paper thumbnail of The Dense Matter Equation of State from Neutron Star Radius and Mass Measurements

The Astrophysical Journal, 2016

Research paper thumbnail of X-ray and Optical Studies of SAX J1808.4-3658 in Quiescence

AIP Conference Proceedings, 2008

ABSTRACT

Research paper thumbnail of Hubble Space Telescope Advanced Camera for Surveys Imaging of ω Centauri: Optical Counterpart for the Quiescent Low‐Mass X‐Ray Binary

The Astrophysical Journal, Sep 20, 2004

We report the discovery of an optical counterpart to a quiescent neutron star in the globular clu... more We report the discovery of an optical counterpart to a quiescent neutron star in the globular cluster omega Centauri (NGC 5139). The star was found as part of our wide-field imaging study of omega Cen using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. Its magnitude and color (R625=25.2, B435-R625=1.5) place it more than 1.5 mag to

Research paper thumbnail of Cataclysmic Variables in Globular Clusters, the Galactic Center, and Local Space

AIP Conference Proceedings, 2008

Research paper thumbnail of Chandra localisation of IGR J17361-4441 in the globular cluster NGC 6388

The Astronomer S Telegram, Sep 1, 2011

We report on a 2.5 ks Chandra observation of IGR J17361-4441 (ATel #3565, #3566, #3595, #3617) th... more We report on a 2.5 ks Chandra observation of IGR J17361-4441 (ATel #3565, #3566, #3595, #3617) that began on 2011-08-29 at 12:53 UT. The observation was taken with the ACIS S3 chip in half-chip subarray imaging mode. We use the CIAO tool wavdetect on a 0.5-6 keV image to determine the locations of the transient and several other sources in