| 1. |
- Blanton, Michael R., et al.
(författare)
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Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
- 2017
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Ingår i: Astronomical Journal. - : IOP Publishing Ltd. - 0004-6256 .- 1538-3881. ; 154:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and. high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z similar to 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z similar to 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs. and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the. Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.
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| 2. |
- Abolfathi, Bela, et al.
(författare)
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The Fourteenth Data Release of the Sloan Digital Sky Survey : First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
- 2018
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Ingår i: Astrophysical Journal Supplement Series. - : IOP Publishing Ltd. - 0067-0049 .- 1538-4365. ; 235:2
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Tidskriftsartikel (refereegranskat)abstract
- The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.
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| 3. |
- Torne, Pablo, et al.
(författare)
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A Search for Pulsars around Sgr A* in the First Event Horizon Telescope Data Set
- 2023
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Ingår i: Astrophysical Journal. - 1538-4357 .- 0004-637X. ; 959:1
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Tidskriftsartikel (refereegranskat)abstract
- In 2017 the Event Horizon Telescope (EHT) observed the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A*), at a frequency of 228.1 GHz (lambda = 1.3 mm). The fundamental physics tests that even a single pulsar orbiting Sgr A* would enable motivate searching for pulsars in EHT data sets. The high observing frequency means that pulsars-which typically exhibit steep emission spectra-are expected to be very faint. However, it also negates pulse scattering, an effect that could hinder pulsar detections in the Galactic center. Additionally, magnetars or a secondary inverse Compton emission could be stronger at millimeter wavelengths than at lower frequencies. We present a search for pulsars close to Sgr A* using the data from the three most sensitive stations in the EHT 2017 campaign: the Atacama Large Millimeter/submillimeter Array, the Large Millimeter Telescope, and the IRAM 30 m Telescope. We apply three detection methods based on Fourier-domain analysis, the fast folding algorithm, and single-pulse searches targeting both pulsars and burst-like transient emission. We use the simultaneity of the observations to confirm potential candidates. No new pulsars or significant bursts were found. Being the first pulsar search ever carried out at such high radio frequencies, we detail our analysis methods and give a detailed estimation of the sensitivity of the search. We conclude that the EHT 2017 observations are only sensitive to a small fraction (less than or similar to 2.2%) of the pulsars that may exist close to Sgr A*, motivating further searches for fainter pulsars in the region.
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| 4. |
- Rosen, Raymond C., et al.
(författare)
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Quality of Life and Sexual Function Benefits of Long-Term Testosterone Treatment : Longitudinal Results From the Registry of Hypogonadism in Men (RHYME)
- 2017
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Ingår i: Journal of Sexual Medicine. - : WILEY. - 1743-6095 .- 1743-6109. ; 14:9, s. 1104-1115
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Tidskriftsartikel (refereegranskat)abstract
- Background: The benefits and risks of long-term testosterone administration have been a topic of much scientific and regulatory interest in recent years. Aim: To assess long-term quality of life (QOL) and sexual function benefits of testosterone replacement therapy (TRT) prospectively in a diverse, multinational cohort of men with hypogonadism. Methods: A multinational patient registry was used to assess long-term changes associated with TRT in middle-age and older men with hypogonadism. Comprehensive evaluations were conducted at 6, 12, 24, and 36 months after enrollment into the registry. Outcomes: QOL and sexual function were evaluated by validated measures, including the Aging Males' Symptom (AMS) Scale and the International Index of Erectile Function (IIEF). Results: A total of 999 previously untreated men with hypogonadism were enrolled at 25 European centers, 750 of whom received TRT at at least one visit during the period of observation. Patients on TRT reported rapid and sustained improvements in QOL, with fewer sexual, psychological, and somatic symptoms. Modest improvements in QOL and sexual function, including erectile function, also were noted in RHYME patients not on TRT, although treated patients showed consistently greater benefit over time in all symptom domains compared with untreated patients. AMS total scores for patients on TRT were 32.8 (95% confidence interval = 31.3-34.4) compared with 36.6 (95% confidence interval = 34.8-38.5) for untreated patients (P < .001). Small but significant improvements in IIEF scores over time also were noted with TRT. Approximately 25% of treated and untreated men also used phosphodiesterase type 5 inhibitors, with notable differences in the frequency of phosphodiesterase type 5 inhibitor prescription use according to physician specialty and geographic site location. Clinical Implications: TRT-related benefits in QOL and sexual function are well maintained for up to 36 months after initiation of treatment. Strengths and Limitations: The major strengths are the large, diverse patient population being treated in multidisciplinary clinical settings. The major limitation is the frequency of switching from one formulation to another. Conclusion: Overall, we confirmed the broad and sustained benefits of TRT across major QOL dimensions, including sexual, somatic, and psychological health, which were sustained over 36 months in our treatment cohort. Copyright (C) 2017, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
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