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Title: DISCOVERY OF AN ACCRETING MILLISECOND PULSAR IN THE ECLIPSING BINARY SYSTEM SWIFT J1749.4-2807

Abstract

We report on the discovery and the timing analysis of the first eclipsing accretion-powered millisecond X-ray pulsar (AMXP): SWIFT J1749.4-2807. The neutron star rotates at a frequency of {approx}517.9 Hz and is in a binary system with an orbital period of 8.8 hr and a projected semimajor axis of {approx}1.90 lt-s. Assuming a neutron star between 0.8 and 2.2 M{sub sun} and using the mass function of the system and the eclipse half-angle, we constrain the mass of the companion and the inclination of the system to be in the {approx}0.46-0.81 M{sub sun} and {approx} 74.{sup 0}4-77.{sup 0}3 range, respectively. To date, this is the tightest constraint on the orbital inclination of any AMXP. As in other AMXPs, the pulse profile shows harmonic content up to the third overtone. However, this is the first AMXP to show a first overtone with rms amplitudes between {approx}6% and {approx}23%, which is the strongest ever seen and which can be more than two times stronger than the fundamental. The fact that SWIFT J1749.4-2807 is an eclipsing system that shows uncommonly strong harmonic content suggests that it might be the best source to date to set constraints on neutron star properties including compactness andmore » geometry.« less

Authors:
; ; ; ; ; ; ; ; ; ;  [1];  [2];  [3];  [4];  [5]
  1. Astronomical Institute, 'Anton Pannekoek', University of Amsterdam, Science Park 904, 1098XH, Amsterdam (Netherlands)
  2. Massachusetts Institute of Technology-Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States)
  3. Institut de Ciencies de l'Espai (ICE, CSIC-IEEC), Campus UAB, Facultat de Ciencies, Torre C5-parell, 2a planta, 08193, Bellaterra (Barcelona) (Spain)
  4. School of Physics and Astronomy, University of Southampton, Southampton, Hampshire SO17 1BJ (United Kingdom)
  5. Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen (Netherlands)
Publication Date:
OSTI Identifier:
21560557
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal Letters
Additional Journal Information:
Journal Volume: 727; Journal Issue: 1; Other Information: DOI: 10.1088/2041-8205/727/1/L18; Journal ID: ISSN 2041-8205
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ECLIPSE; MASS; NEUTRON STARS; PULSARS; X RADIATION; COSMIC RADIO SOURCES; ELECTROMAGNETIC RADIATION; IONIZING RADIATIONS; RADIATIONS; STARS

Citation Formats

Altamirano, D, Cavecchi, Y, Patruno, A, Watts, A, Degenaar, N, Kalamkar, M, Van der Klis, M, Armas Padilla, M, Kaur, R, Yang, Y J, Wijnands, R, Linares, M, Rea, N, Casella, P, and Soleri, P. DISCOVERY OF AN ACCRETING MILLISECOND PULSAR IN THE ECLIPSING BINARY SYSTEM SWIFT J1749.4-2807. United States: N. p., 2011. Web. doi:10.1088/2041-8205/727/1/L18.
Altamirano, D, Cavecchi, Y, Patruno, A, Watts, A, Degenaar, N, Kalamkar, M, Van der Klis, M, Armas Padilla, M, Kaur, R, Yang, Y J, Wijnands, R, Linares, M, Rea, N, Casella, P, & Soleri, P. DISCOVERY OF AN ACCRETING MILLISECOND PULSAR IN THE ECLIPSING BINARY SYSTEM SWIFT J1749.4-2807. United States. https://doi.org/10.1088/2041-8205/727/1/L18
Altamirano, D, Cavecchi, Y, Patruno, A, Watts, A, Degenaar, N, Kalamkar, M, Van der Klis, M, Armas Padilla, M, Kaur, R, Yang, Y J, Wijnands, R, Linares, M, Rea, N, Casella, P, and Soleri, P. 2011. "DISCOVERY OF AN ACCRETING MILLISECOND PULSAR IN THE ECLIPSING BINARY SYSTEM SWIFT J1749.4-2807". United States. https://doi.org/10.1088/2041-8205/727/1/L18.
@article{osti_21560557,
title = {DISCOVERY OF AN ACCRETING MILLISECOND PULSAR IN THE ECLIPSING BINARY SYSTEM SWIFT J1749.4-2807},
author = {Altamirano, D and Cavecchi, Y and Patruno, A and Watts, A and Degenaar, N and Kalamkar, M and Van der Klis, M and Armas Padilla, M and Kaur, R and Yang, Y J and Wijnands, R and Linares, M and Rea, N and Casella, P and Soleri, P},
abstractNote = {We report on the discovery and the timing analysis of the first eclipsing accretion-powered millisecond X-ray pulsar (AMXP): SWIFT J1749.4-2807. The neutron star rotates at a frequency of {approx}517.9 Hz and is in a binary system with an orbital period of 8.8 hr and a projected semimajor axis of {approx}1.90 lt-s. Assuming a neutron star between 0.8 and 2.2 M{sub sun} and using the mass function of the system and the eclipse half-angle, we constrain the mass of the companion and the inclination of the system to be in the {approx}0.46-0.81 M{sub sun} and {approx} 74.{sup 0}4-77.{sup 0}3 range, respectively. To date, this is the tightest constraint on the orbital inclination of any AMXP. As in other AMXPs, the pulse profile shows harmonic content up to the third overtone. However, this is the first AMXP to show a first overtone with rms amplitudes between {approx}6% and {approx}23%, which is the strongest ever seen and which can be more than two times stronger than the fundamental. The fact that SWIFT J1749.4-2807 is an eclipsing system that shows uncommonly strong harmonic content suggests that it might be the best source to date to set constraints on neutron star properties including compactness and geometry.},
doi = {10.1088/2041-8205/727/1/L18},
url = {https://www.osti.gov/biblio/21560557}, journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 1,
volume = 727,
place = {United States},
year = {Thu Jan 20 00:00:00 EST 2011},
month = {Thu Jan 20 00:00:00 EST 2011}
}