skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey

Abstract

We report the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first year data of the Dark Energy Survey (DES). The Eridanus-Phoenix (EriPhe) overdensity is centered around l~285 deg and b~-60 deg and spans at least 30 deg in longitude and 10 deg in latitude. The Poisson significance of the detection is at least 9 sigma. The stellar population in the overdense region is similar in brightness and color to that of the nearby globular cluster NGC 1261, indicating that the heliocentric distance of EriPhe is about d~16 kpc. The extent of EriPhe in projection is therefore at least ~4 kpc by ~3 kpc. On the sky, this overdensity is located between NGC 1261 and a new stellar stream discovered by DES at a similar heliocentric distance, the so-called Phoenix Stream. Given their similar distance and proximity to each other, it is possible that these three structures may be kinematically associated. Alternatively, the EriPhe overdensity is morphologically similar to the Virgo overdensity and the Hercules-Aquila cloud, which also lie at a similar Galactocentric distance. These three overdensities lie along a polar plane separated by ~120 deg andmore » may share a common origin. Spectroscopic follow-up observations of the stars in EriPhe are required to fully understand the nature of this overdensity.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
The DES Collaboration
OSTI Identifier:
1234896
Alternate Identifier(s):
OSTI ID: 1257727
Report Number(s):
FERMILAB-PUB-15-392-AE; SLAC-PUB-16571
Journal ID: ISSN 1538-4357; arXiv eprint number arXiv:1509.04296
Grant/Contract Number:  
AC02-07CH11359; AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Volume: 817; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; Astrophysics; galaxy: formation; galaxy: halo; galaxy: structure; galaxy: local group

Citation Formats

Li, T. S., Balbinot, E., Mondrik, N., Marshall, J. L., Yanny, B., Bechtol, K., Drlica-Wagner, A., Oscar, D., Santiago, B., Simon, J. D., Vivas, A. K., Walker, A. R., Wang, M. Y., Abbott, T. M. C., Abdalla, F. B., Benoit-Lévy, A., Bernstein, G. M., Bertin, E., Brooks, D., Burke, D. L., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Costa, L. N. da, DePoy, D. L., Desai, S., Diehl, H. T., Doel, P., Estrada, J., Finley, D. A., Flaugher, B., Frieman, J., Gruen, D., Gruendl, R. A., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuropatkin, N., Lahav, O., Maia, M. A. G., March, M., Martini, P., Ogando, R., Plazas, A. A., Reil, K., Romer, A. K., Roodman, A., Sanchez, E., Scarpine, V., Schubnell, M., Sevilla-Noarbe, I., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Tucker, D., and Zhang, Y.. Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey. United States: N. p., 2016. Web. doi:10.3847/0004-637X/817/2/135.
Li, T. S., Balbinot, E., Mondrik, N., Marshall, J. L., Yanny, B., Bechtol, K., Drlica-Wagner, A., Oscar, D., Santiago, B., Simon, J. D., Vivas, A. K., Walker, A. R., Wang, M. Y., Abbott, T. M. C., Abdalla, F. B., Benoit-Lévy, A., Bernstein, G. M., Bertin, E., Brooks, D., Burke, D. L., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Costa, L. N. da, DePoy, D. L., Desai, S., Diehl, H. T., Doel, P., Estrada, J., Finley, D. A., Flaugher, B., Frieman, J., Gruen, D., Gruendl, R. A., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuropatkin, N., Lahav, O., Maia, M. A. G., March, M., Martini, P., Ogando, R., Plazas, A. A., Reil, K., Romer, A. K., Roodman, A., Sanchez, E., Scarpine, V., Schubnell, M., Sevilla-Noarbe, I., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Tucker, D., & Zhang, Y.. Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey. United States. doi:10.3847/0004-637X/817/2/135.
Li, T. S., Balbinot, E., Mondrik, N., Marshall, J. L., Yanny, B., Bechtol, K., Drlica-Wagner, A., Oscar, D., Santiago, B., Simon, J. D., Vivas, A. K., Walker, A. R., Wang, M. Y., Abbott, T. M. C., Abdalla, F. B., Benoit-Lévy, A., Bernstein, G. M., Bertin, E., Brooks, D., Burke, D. L., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Costa, L. N. da, DePoy, D. L., Desai, S., Diehl, H. T., Doel, P., Estrada, J., Finley, D. A., Flaugher, B., Frieman, J., Gruen, D., Gruendl, R. A., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuropatkin, N., Lahav, O., Maia, M. A. G., March, M., Martini, P., Ogando, R., Plazas, A. A., Reil, K., Romer, A. K., Roodman, A., Sanchez, E., Scarpine, V., Schubnell, M., Sevilla-Noarbe, I., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Tucker, D., and Zhang, Y.. Wed . "Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey". United States. doi:10.3847/0004-637X/817/2/135. https://www.osti.gov/servlets/purl/1234896.
@article{osti_1234896,
title = {Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey},
author = {Li, T. S. and Balbinot, E. and Mondrik, N. and Marshall, J. L. and Yanny, B. and Bechtol, K. and Drlica-Wagner, A. and Oscar, D. and Santiago, B. and Simon, J. D. and Vivas, A. K. and Walker, A. R. and Wang, M. Y. and Abbott, T. M. C. and Abdalla, F. B. and Benoit-Lévy, A. and Bernstein, G. M. and Bertin, E. and Brooks, D. and Burke, D. L. and Rosell, A. Carnero and Kind, M. Carrasco and Carretero, J. and Costa, L. N. da and DePoy, D. L. and Desai, S. and Diehl, H. T. and Doel, P. and Estrada, J. and Finley, D. A. and Flaugher, B. and Frieman, J. and Gruen, D. and Gruendl, R. A. and Gutierrez, G. and Honscheid, K. and James, D. J. and Kuehn, K. and Kuropatkin, N. and Lahav, O. and Maia, M. A. G. and March, M. and Martini, P. and Ogando, R. and Plazas, A. A. and Reil, K. and Romer, A. K. and Roodman, A. and Sanchez, E. and Scarpine, V. and Schubnell, M. and Sevilla-Noarbe, I. and Smith, R. C. and Soares-Santos, M. and Sobreira, F. and Suchyta, E. and Swanson, M. E. C. and Tarle, G. and Tucker, D. and Zhang, Y.},
abstractNote = {We report the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first year data of the Dark Energy Survey (DES). The Eridanus-Phoenix (EriPhe) overdensity is centered around l~285 deg and b~-60 deg and spans at least 30 deg in longitude and 10 deg in latitude. The Poisson significance of the detection is at least 9 sigma. The stellar population in the overdense region is similar in brightness and color to that of the nearby globular cluster NGC 1261, indicating that the heliocentric distance of EriPhe is about d~16 kpc. The extent of EriPhe in projection is therefore at least ~4 kpc by ~3 kpc. On the sky, this overdensity is located between NGC 1261 and a new stellar stream discovered by DES at a similar heliocentric distance, the so-called Phoenix Stream. Given their similar distance and proximity to each other, it is possible that these three structures may be kinematically associated. Alternatively, the EriPhe overdensity is morphologically similar to the Virgo overdensity and the Hercules-Aquila cloud, which also lie at a similar Galactocentric distance. These three overdensities lie along a polar plane separated by ~120 deg and may share a common origin. Spectroscopic follow-up observations of the stars in EriPhe are required to fully understand the nature of this overdensity.},
doi = {10.3847/0004-637X/817/2/135},
journal = {The Astrophysical Journal (Online)},
issn = {1538-4357},
number = 2,
volume = 817,
place = {United States},
year = {2016},
month = {1}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 7 works
Citation information provided by
Web of Science

Save / Share: