TY  - JOUR
A1  - Ivanov, Valentin D.
A1  - Cioni, Maria-Rosa L.
A1  - Bekki, Kenji
A1  - de Grijs, Richard
A1  - Emerson, Jim
A1  - Gibson, Brad K.
A1  - Kamath, Devika
A1  - van Loon, Jacco Th.
A1  - Piatti, Andres E.
A1  - For, Bi-Qing
T1  - New quasars behind the Magellanic Clouds. Spectroscopic confirmation of near-infrared selected candidates
JF  - Current biology
N2  - Context. Quasi-stellar objects (quasars) located behind nearby galaxies provide an excellent absolute reference system for astrometric studies, but they are difficult to identify because of fore-and background contamination. Deep wide-field, high angular resolution surveys spanning the entire area of nearby galaxies are needed to obtain a complete census of such quasars. Aims. We embarked on a program to expand the quasar reference system behind the Large and the Small Magellanic Clouds, the Magellanic Bridge, and the Magellanic Stream that connects the Clouds with the Milky Way. Methods. Hundreds of quasar candidates were selected based on their near-infrared colors and variability properties from the ongoing public ESO VISTA Magellanic Clouds survey. A subset of 49 objects was followed up with optical spectroscopy. Results. We confirmed the quasar nature of 37 objects (34 new identifications): four are low redshift objects, three are probably stars, and the remaining three lack prominent spectral features for a secure classification. The bona fide quasars, identified from their broad emisison lines, are located as follows: 10 behind the LMC, 13 behind the SMC, and 14 behind the Bridge. The quasars span a redshift range from z similar to 0.5 to z similar to 4.1. Conclusions. Upon completion the VMC survey is expected to yield a total of similar to 1500 quasars with Y < 19.32 mag, J < 19.09 mag, and K-s < 18.04 mag.
KW  - surveys
KW  - infrared: galaxies
KW  - quasars: general
KW  - Magellanic Clouds
Y1  - 2016
U6  - https://doi.org/10.1051/0004-6361/201527398
SN  - 1432-0746
VL  - 588
PB  - EDP Sciences
CY  - Les Ulis
ER  - 
TY  - JOUR
A1  - Piatti, Andres E.
A1  - de Grijs, Richard
A1  - Ripepi, Vincenzo
A1  - Ivanov, Valentin D.
A1  - Cioni, Maria-Rosa L.
A1  - Marconi, Marcella
A1  - Rubele, Stefano
A1  - Bekki, Kenji
A1  - For, Bi-Qing
T1  - The VMC survey - XVI. Spatial variation of the cluster formation activity in the innermost regions of the Large Magellanic Cloud
JF  - Monthly notices of the Royal Astronomical Society
KW  - techniques: photometric
KW  - galaxies: individual: LMC
KW  - Magellanic Clouds
Y1  - 2015
U6  - https://doi.org/10.1093/mnras/stv2054
SN  - 0035-8711
SN  - 1365-2966
VL  - 454
IS  - 1
SP  - 839
EP  - 848
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Zhang, Chaoli
A1  - Li, Chengyuan
A1  - de Grijs, Richard
A1  - Bekki, Kenji
A1  - Deng, Licai
A1  - Zaggia, Simone
A1  - Rubele, Stefano
A1  - Piatti, Andres E.
A1  - Cioni, Maria-Rosa L.
A1  - Emerson, Jim
A1  - For, Bi-Qing
A1  - Ripepi, Vincenzo
A1  - Marconi, Marcella
A1  - Ivanov, Valentin D.
A1  - Chen, Li
T1  - The vmc survey. XVIII. radial dependence of the Low-Mass, 0.55-0.82M(circle dot) stellar mass function in the galactic globular cluster 47 tucanae
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
KW  - galaxies: clusters: individual (47 Tucanae)
KW  - globular clusters: general
KW  - Hertzsprung-Russell and C-M diagrams
KW  - stars: low-mass
KW  - stars: luminosity function, mass function
Y1  - 2015
U6  - https://doi.org/10.1088/0004-637X/815/2/95
SN  - 0004-637X
SN  - 1538-4357
VL  - 815
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  -