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Title: THE OPTICAL COMPANION TO THE BINARY MILLISECOND PULSAR J1824-2452H IN THE GLOBULAR CLUSTER M28

Abstract

We report on the optical identification of the companion star to the eclipsing millisecond pulsar (MSP) PSR J1824-2452H in the galactic globular cluster M28 (NGC 6626). This star is at only 0.''2 from the nominal position of the pulsar and it shows optical variability ({approx}0.25 mag) that nicely correlates with the pulsar orbital period. It is located on the blue side of the cluster main sequence, {approx}1.5 mag fainter than the turnoff point. The observed light curve shows two distinct and asymmetric minima, suggesting that the companion star is suffering tidal distortion from the pulsar. This discovery increases the number of non-degenerate MSP companions optically identified so far in globular clusters (four out of seven), suggesting that these systems could be a common outcome of the pulsar recycling process, at least in dense environments where they can be originated by exchange interactions.

Authors:
; ; ;  [1];  [2]; ;  [3];  [4]; ;  [5];  [6]
  1. Dipartimento di Astronomia, Universita degli Studi di Bologna, via Ranzani 1, I-40127 Bologna (Italy)
  2. Astronomy Department, University of Virginia, P.O. Box 3818, Charlottesville, VA 22903-0818 (United States)
  3. INAF-Osservatorio Astronomico di Cagliari, localita Poggio dei Pini, strada 54, I-09012 Capoterra (Italy)
  4. Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)
  5. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC, V6T 1Z1 (Canada)
  6. National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States)
Publication Date:
OSTI Identifier:
21474371
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 725; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/725/1/1165
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASYMMETRY; EXCHANGE INTERACTIONS; NEUTRON STARS; PULSARS; STAR EVOLUTION; COSMIC RADIO SOURCES; EVOLUTION; INTERACTIONS; STARS

Citation Formats

Pallanca, C., Dalessandro, E., Ferraro, F. R., Lanzoni, B., Rood, R. T., Possenti, A., D'Amico, N., Freire, P. C., Stairs, I., Begin, S., and Ransom, S. M.. THE OPTICAL COMPANION TO THE BINARY MILLISECOND PULSAR J1824-2452H IN THE GLOBULAR CLUSTER M28. United States: N. p., 2010. Web. doi:10.1088/0004-637X/725/1/1165.
Pallanca, C., Dalessandro, E., Ferraro, F. R., Lanzoni, B., Rood, R. T., Possenti, A., D'Amico, N., Freire, P. C., Stairs, I., Begin, S., & Ransom, S. M.. THE OPTICAL COMPANION TO THE BINARY MILLISECOND PULSAR J1824-2452H IN THE GLOBULAR CLUSTER M28. United States. doi:10.1088/0004-637X/725/1/1165.
Pallanca, C., Dalessandro, E., Ferraro, F. R., Lanzoni, B., Rood, R. T., Possenti, A., D'Amico, N., Freire, P. C., Stairs, I., Begin, S., and Ransom, S. M.. 2010. "THE OPTICAL COMPANION TO THE BINARY MILLISECOND PULSAR J1824-2452H IN THE GLOBULAR CLUSTER M28". United States. doi:10.1088/0004-637X/725/1/1165.
@article{osti_21474371,
title = {THE OPTICAL COMPANION TO THE BINARY MILLISECOND PULSAR J1824-2452H IN THE GLOBULAR CLUSTER M28},
author = {Pallanca, C. and Dalessandro, E. and Ferraro, F. R. and Lanzoni, B. and Rood, R. T. and Possenti, A. and D'Amico, N. and Freire, P. C. and Stairs, I. and Begin, S. and Ransom, S. M.},
abstractNote = {We report on the optical identification of the companion star to the eclipsing millisecond pulsar (MSP) PSR J1824-2452H in the galactic globular cluster M28 (NGC 6626). This star is at only 0.''2 from the nominal position of the pulsar and it shows optical variability ({approx}0.25 mag) that nicely correlates with the pulsar orbital period. It is located on the blue side of the cluster main sequence, {approx}1.5 mag fainter than the turnoff point. The observed light curve shows two distinct and asymmetric minima, suggesting that the companion star is suffering tidal distortion from the pulsar. This discovery increases the number of non-degenerate MSP companions optically identified so far in globular clusters (four out of seven), suggesting that these systems could be a common outcome of the pulsar recycling process, at least in dense environments where they can be originated by exchange interactions.},
doi = {10.1088/0004-637X/725/1/1165},
journal = {Astrophysical Journal},
number = 1,
volume = 725,
place = {United States},
year = 2010,
month =
}
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