TY - JOUR
T1 - The next generation virgo cluster survey-infrared (NGVS-IR). I. A new near-ultraviolet, optical, and near-infrared globular cluster selection tool
AU - Muñoz, Roberto P.
AU - Puzia, Thomas H.
AU - Lançon, Ariane
AU - Peng, Eric W.
AU - Côté, Patrick
AU - Ferrarese, Laura
AU - Blakeslee, John P.
AU - Mei, Simona
AU - Cuillandre, Jean Charles
AU - Hudelot, Patrick
AU - Courteau, Stéphane
AU - Duc, Pierre Alain
AU - Balogh, Michael L.
AU - Boselli, Alessandro
AU - Bournaud, Frédéric
AU - Carlberg, Raymond G.
AU - Chapman, Scott C.
AU - Durrell, Patrick
AU - Eigenthaler, Paul
AU - Emsellem, Eric
AU - Gavazzi, Giuseppe
AU - Gwyn, Stephen
AU - Huertas-Company, Marc
AU - Ilbert, Olivier
AU - Jordán, Andrés
AU - Läsker, Ronald
AU - Licitra, Rossella
AU - Liu, Chengze
AU - Macarthur, Lauren
AU - McConnachie, Alan
AU - McCracken, Henry Joy
AU - Mellier, Yannick
AU - Peng, Chien Y.
AU - Raichoor, Anand
AU - Taylor, Matthew A.
AU - Tonry, John L.
AU - Tully, R. Brent
AU - Zhang, Hongxin
PY - 2014/1
Y1 - 2014/1
N2 - The NGVS-IR project (Next Generation Virgo Cluster Survey-Infrared) is a contiguous, near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). In its current state, NGVS-IR consists of Ks -band imaging of 4 deg2 centered on M87 and J- and Ks -band imaging of 16 deg2 covering the region between M49 and M87. We present observations of the central 4 deg2 centered on Virgo's core region. The data were acquired with WIRCam on the Canada-France-Hawaii Telescope, and the total integration time was 41 hr distributed over 34 contiguous tiles. A survey-specific strategy was designed to account for extended galaxies while still measuring accurate sky brightness within the survey area. The average 5σ limiting magnitude is Ks = 24.4 AB mag, and the 50% completeness limit is Ks = 23.75 AB mag for point-source detections, when using only images with better than 0.″7 seeing (median seeing 0.″54). Star clusters are marginally resolved in these image stacks, and Virgo galaxies with AB mag arcsec-2 are detected. Combining the Ks data with optical and ultraviolet data, we build the uiKs color-color diagram, which allows a very clean color-based selection of globular clusters in Virgo. This diagnostic plot will provide reliable globular cluster candidates for spectroscopic follow-up campaigns, needed to continue the exploration of Virgo's photometric and kinematic substructures, and will help the design of future searches for globular clusters in extragalactic systems. We show that the new uiKs diagram displays significantly clearer substructure in the distribution of stars, globular clusters, and galaxies than the gzKs diagram - the NGVS + NGVS-IR equivalent of the BzK diagram that is widely used in cosmological surveys. Equipped with this powerful new tool, future NGVS-IR investigations based on the uiKs diagram will address the mapping and analysis of extended structures and compact stellar systems in and around Virgo galaxies.
AB - The NGVS-IR project (Next Generation Virgo Cluster Survey-Infrared) is a contiguous, near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). In its current state, NGVS-IR consists of Ks -band imaging of 4 deg2 centered on M87 and J- and Ks -band imaging of 16 deg2 covering the region between M49 and M87. We present observations of the central 4 deg2 centered on Virgo's core region. The data were acquired with WIRCam on the Canada-France-Hawaii Telescope, and the total integration time was 41 hr distributed over 34 contiguous tiles. A survey-specific strategy was designed to account for extended galaxies while still measuring accurate sky brightness within the survey area. The average 5σ limiting magnitude is Ks = 24.4 AB mag, and the 50% completeness limit is Ks = 23.75 AB mag for point-source detections, when using only images with better than 0.″7 seeing (median seeing 0.″54). Star clusters are marginally resolved in these image stacks, and Virgo galaxies with AB mag arcsec-2 are detected. Combining the Ks data with optical and ultraviolet data, we build the uiKs color-color diagram, which allows a very clean color-based selection of globular clusters in Virgo. This diagnostic plot will provide reliable globular cluster candidates for spectroscopic follow-up campaigns, needed to continue the exploration of Virgo's photometric and kinematic substructures, and will help the design of future searches for globular clusters in extragalactic systems. We show that the new uiKs diagram displays significantly clearer substructure in the distribution of stars, globular clusters, and galaxies than the gzKs diagram - the NGVS + NGVS-IR equivalent of the BzK diagram that is widely used in cosmological surveys. Equipped with this powerful new tool, future NGVS-IR investigations based on the uiKs diagram will address the mapping and analysis of extended structures and compact stellar systems in and around Virgo galaxies.
KW - galaxies: clusters: individual (Virgo)
KW - galaxies: distances and redshifts
KW - galaxies: luminosity function, mass function
KW - galaxies: photometry
KW - galaxies: star clusters: general
UR - http://www.scopus.com/inward/record.url?scp=84893204723&partnerID=8YFLogxK
U2 - 10.1088/0067-0049/210/1/4
DO - 10.1088/0067-0049/210/1/4
M3 - Article
AN - SCOPUS:84893204723
SN - 0067-0049
VL - 210
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 1
M1 - 4
ER -