Keiichi Umetsu

Dr. Keiichi Umetsu


Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 September 2017 in Publications of the Astronomical Society of Japan
Verified
Journal Article
Open access
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HAHiroaki Aihara
Hiroaki Aihara
NANobuo Arimoto
Nobuo Arimoto
RARobert Armstrong
Robert Armstrong
SAStéphane Arnouts
Stéphane Arnouts
NBNeta A Bahcall
Neta A Bahcall
SYSuraphong Yuma
Suraphong Yuma
Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2-m Subaru telescope on the summit of Mauna Kea in Hawaii. A team of scientists from Japan, Taiwan, and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg2 in five broad bands (grizy), with a 5 σ point-source depth of r ≈ 26. The Deep layer covers a total of 26 deg2 in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg2). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey.

14 March 2012 in The Astrophysical Journal Supplement Series
Verified
Journal Article
Closed access
MPMarc Postman
Marc Postman
DCDan Coe
Dan Coe
NBNarciso Benítez
Narciso Benítez
LBLarry Bradley
Larry Bradley
TBTom Broadhurst
Tom Broadhurst
AWArjen Van der Wel
Arjen Van der Wel

12 October 2017 in Publications of the Astronomical Society of Japan
Verified
Journal Article
Closed access
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HAHiroaki Aihara
Hiroaki Aihara
RARobert Armstrong
Robert Armstrong
SBSteven Bickerton
Steven Bickerton
JBJames Bosch
James Bosch
JCJean Coupon
Jean Coupon
SYSuraphong Yuma
Suraphong Yuma
The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered imaging survey aimed at addressing some of the most important outstanding questions in astronomy today, including the nature of dark matter and dark energy. The survey has been awarded 300 nights of observing time at the Subaru Telescope, and it started in 2014 March. This paper presents the first public data release of HSC-SSP. This release includes data taken in the first 1.7 yr of observations (61.5 nights), and each of the Wide, Deep, and UltraDeep layers covers about 108, 26, and 4 square degrees down to depths of i ∼ 26.4, ∼26.5, and ∼27.0 mag, respectively (5 σ for point sources). All the layers are observed in five broad bands (grizy), and the Deep and UltraDeep layers are observed in narrow bands as well. We achieve an impressive image quality of 0$${^{\prime\prime}_{.}}$$6 in the i band in the Wide layer. We show that we achieve 1%–2% point spread function (PSF) photometry (root mean square) both internally and externally (against Pan-STARRS1), and ∼10 mas and 40 mas internal and external astrometric accuracy, respectively. Both the calibrated images and catalogs are made available to the community through dedicated user interfaces and database servers. In addition to the pipeline products, we also provide value-added products such as photometric redshifts and a collection of public spectroscopic redshifts. Detailed descriptions of all the data can be found online. The data release website is https://hsc-release.mtk.nao.ac.jp.

1 March 2015 in The Astrophysical Journal
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Journal Article
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AZAdi Zitrin
Adi Zitrin
AFAgnese Fabris
Agnese Fabris
JMJulian Merten
Julian Merten
PMPeter Melchior
Peter Melchior
MMMassimo Meneghetti
Massimo Meneghetti
JMJohn Moustakas
John Moustakas

4 March 2014 in The Astrophysical Journal
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Journal Article
Closed access
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RSR. Smit
R. Smit
RBR. J. Bouwens
R. J. Bouwens
ILI. Labbé
I. Labbé
WZW. Zheng
W. Zheng
LBL. Bradley
L. Bradley
SSS. Seitz
S. Seitz

28 October 2014 in The Astrophysical Journal
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Journal Article
Closed access
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KUKeiichi Umetsu
Keiichi Umetsu
EMElinor Medezinski
Elinor Medezinski
MNMario Nonino
Mario Nonino
JMJulian Merten
Julian Merten
MPMarc Postman
Marc Postman
AZAdi Zitrin
Adi Zitrin