High-resolution extinction map in the direction of the strongly obscured bulge fossil fragment Liller 1

Abstract

We used optical images acquired with the Wide Field Camera of the Advanced Camera for Surveys onboard the Hubble Space Telescope and near-infrared data from GeMS/GSAOI to construct a high-resolution extinction map in the direction of the bulge stellar system Liller 1. In spite of its appearance of a globular cluster, Liller 1 has been recently found to harbor two stellar populations with remarkably different ages, and it is the second complex stellar system with similar properties (after Terzan5) discovered in the bulge, thus defining a new class of objects: the Bulge Fossil Fragments. Because of its location in the inner bulge of the Milky Way, very close to the Galactic plane, Liller 1 is strongly affected by large and variable extinction. The simultaneous study of both the optical and the near-infrared color-magnitude diagrams revealed that the extinction coefficient R${}_V$ in the direction of Liller 1 has a much smaller value than commonly assumed for diffuse interstellar medium (R${}_V=2.5$, instead of 3.1), in agreement with previous findings along different light paths to the Galactic bulge. The derived differential reddening map has a spatial resolution ranging from $1^{\prime \prime }$ to $3^{\prime \prime }$ over a field of view of about $90^{\prime \prime }$X$90^{\prime \prime }$. We found that the absorption clouds show patchy sub-structures with extinction variations as large as $\delta \mathrm{E}(B-V)\sim 0.9$ mag.

Accepted for publication in The Astrophysical Journal; 18 pages, 8 figures, 1 table

References in corpus (20)

• Array Programming with NumPy
• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Bulge Formation by the Coalescence of Giant Clumps in Primordial Disk Galaxies
• Synthetic Stellar Photometry - I. General considerations and new transformations for broad-band systems
• Ceci n'est pas a globular cluster: the metallicity distribution of the stellar system Terzan 5
• Extinction ratios in the inner Galaxy as revealed by the VVV survey
• The age of the young bulge-like population in the stellar system Terzan5: linking the Galactic bulge to the high-z Universe
• Old and young bulges in late-type disk galaxies
• The SINS/zC-SINF Survey of z~2 Galaxy Kinematics: Rest-frame Morphology, Structure, and Colors from Near-infrared Hubble Space Telescope Imaging
• A Deep View of a Fossil Relic in the Galactic Bulge: The Globular Cluster HP1
• A new class of fossil fragments from the hierarchical assembly of the Galactic bulge
• High resolution reddening map in the direction of the stellar system Terzan 5
• Radio timing and optical photometry of the black widow system PSR J1518+0204C in the globular cluster M5
• A panchromatic view of the bulge globular cluster NGC 6569
• Mapping the Interstellar Reddening and Extinction towards Baade's Window Using Minimum Light Colors of ab-type RR Lyrae Stars. Revelations from the De-reddened Color-Magnitude Diagrams
• An extremely low-mass He white dwarf orbiting the millisecond pulsar J1342+2822B in the globular cluster M3
• Digging for relics of the past: the ancient and obscured bulge globular cluster NGC6256
• Radio Timing and Optical Photometry of the Black Widow System PSR J1953+1846A in the Globular Cluster M71
• A complete census of $H\alpha$ emitters in NGC 6397

Cited by in corpus (18)

• Reconstructing the Disrupted Dwarf Galaxy $Gaia$-Sausage/Enceladus Using its Stars and Globular Clusters
• Differential reddening in the direction of 56 Galactic globular clusters
• Discovery of a double sequence of blue straggler stars in the core-collapsed globular cluster NGC 6256
• First evidence of multi-iron sub-populations in the Bulge Fossil Fragment candidate Liller 1
• Digging into the Galactic Bulge: stellar population and structure of the poorly studied cluster NGC 6316
• Clues to the formation of Liller 1 from modeling its complex star formation history
• Unveiling the nature of 12 new low-luminosity Galactic Globular Cluster Candidates
• Internal kinematics and structure of the bulge globular cluster NGC 6569
• A binary-related origin mediated by environmental conditions for blue straggler stars
• A Photometric in-depth look at the core-collapsed globular cluster NGC 6284
• The Bulge Cluster Origin (BulCO) survey at the ESO-VLT: probing the early history of the Milky Way assembling. Design and first results in Liller1
• The bulge globular cluster Terzan 6 as seen from multi-conjugate adaptive optics and HST
• Bulge Fossil Fragments as a new population of factories of gravitational wave sources in the Galaxy
• Probing populations of dark stellar remnants in the globular clusters 47 Tuc and Terzan 5 using pulsar timing
• The multi-age stellar populations of Terzan 5 as revealed by JWST
• Revealing the stellar population of the ultra-obscured Galactic globular cluster Glimpse-C02
• A candidate to the long sought optical counterpart to the Rapid Burster in the bulge fossil fragment Liller 1
• Consensus based Algorithm for Nonparametric Detection of Star Clusters (CANDiSC)