Neutral Hydrogen Absorption Toward XTE J1810-197: the Distance to a Radio-Emitting Magnetar

Abstract

We have used the Green Bank Telescope to measure HI absorption against the anomalous X-ray pulsar XTE J1810-197. Assuming a flat rotation curve, we find that XTE J1810-197 is located at a distance of 3.4(+0.5,-0.7) kpc. For a rotation curve that incorporates a model of the Galactic bar, we obtain a distance of 4.0(+0.3,-0.8) kpc. Using a rotation curve that incorporates a model of the Galactic bar and the spiral arms of the Galaxy, the distance is 3.7(+/-0.6) kpc. These values are consistent with the distance to XTE J1810-197 of about 3.3 kpc derived from its dispersion measure, and estimates of 2-5 kpc obtained from fits to its X-ray spectra. Overall, we determine that XTE J1810-197 is located at a distance of 3.5(+/-0.5) kpc, possibly not far in front of the infrared dark cloud G10.74-0.13. We also used the GBT in an attempt to measure absorption in the OH 1612, 1665, 1667, and 1720 MHz lines against XTE J1810-197. We were unsuccessful in this, mainly because of its declining radio flux density. Analysis of HI 21 cm, OH, and CO(2-1) emission toward XTE J1810-197 allows us to place a lower limit of $N_{\rm H} \ga 4.6 \times 10^{21}$ cm${}^{-2}$ on the non-ionized hydrogen column density to \magnetar, consistent with estimates obtained from fits to its X-ray spectra.

35 pages, 11 figures, 5 Tables Submitted to ApJ

References in corpus (8)

• Transient pulsed radio emission from a magnetar
• Distances to Anomalous X-ray Pulsars using Red Clump Stars
• Milky Way Kinematics: Measurements at the Subcentral Point of the Fourth Quadrant
• Magnetically Dominated Strands of Cold Hydrogen in the Riegel-Crutcher Cloud
• Polarized radio emission from the magnetar XTE J1810-197
• The Magnetar Nature and the Outburst Mechanism of a Transient Anomalous X-ray Pulsar
• Milky Way Gas Dynamics
• Detection of OH absorption against PSR B1718-35

Cited by in corpus (14)

• On Pulsar Distance Measurements and their Uncertainties
• Constraints on the Emission and Viewing Geometry of the Transient Anomalous X-ray Pulsar XTE J1810-197
• The 2018 X-ray and Radio Outburst of Magnetar XTE J1810-197
• A magnetar parallax
• Detection of the magnetar XTE J1810-197 at 150 and 260 GHz with the NIKA2 Kinetic Inductance Detector camera
• Axion Constraints from Quiescent Soft Gamma-ray Emission from Magnetars
• Coherent radio emission from a twisted magnetosphere after magnetar-quake
• Searching for Magnetar Binaries Disrupted by Core-Collapse Supernovae
• Bright X-ray and Radio Pulses from a Recently Reactivated Magnetar
• Detection of OH absorption against PSR B1718-35
• Revealing Hidden Variability in PWNe With Spectral Index Maps
• ALMA discovery of Punctum -- a highly polarized mm source in nuclear starburst galaxy NGC 4945
• Correlation of Burst Behaviour with Magnetar Age
• Characterizing Pulsar Distances Using HI Kinematics