61 research outputs found
Structure in the Disk of epsilon Aurigae: Analysis of the ARCES and TripleSpec data obtained during the 2010 eclipse
Context: Worldwide interest in the recent eclipse of epsilon Aurigae resulted
in the generation of several extensive data sets, including those related to
high resolution spectroscopic monitoring. This lead to the discovery, among
other things, of the existence of a mass transfer stream, seen notably during
third contact. Aims: We explored spectroscopic facets of the mass transfer
stream during third contact, using high resolution spectra obtained with the
ARCES and TripleSpec instruments at Apache Point Observatory. Methods: One
hundred and sixteen epochs of data between 2009 and 2012 were obtained, and
equivalent widths and line velocities measured, selected according to reports
of these being high versus low eccentricity disk lines. These datasets also
enable greater detail to be measured of the mid-eclipse enhancement of the He I
10830A line, and the discovery of the P Cygni shape of the Pa beta line at
third contact. Analysis: We found evidence of higher speed material, associated
with the mass transfer stream, persisting between third and fourth eclipse
contacts. We visualize the disk and stream interaction using SHAPE software,
and use CLOUDY software to estimate that the source of the enhanced He I 10830A
absorption arises from a region with log n = 10 (/cm3) and temperature of
20,000 K consistent with a mid B type central star. Results and Next Steps: Van
Rensbergen binary star evolutionary models are somewhat consistent with the
current binary parameters for the case of a 9 plus 8 solar mass initial binary,
evolving into a 2.3 and 14.11 solar mass end product after 35 Myr. Prior to the
next eclipse, it is possible to make predictions which suggest that continued
monitoring will help resolve standing questions about this binary
The galaxies missed by Hubble and ALMA: the contribution of extremely red galaxies to the cosmic census at 3<z<8
Using deep JWST imaging from JADES, JEMS and SMILES, we characterize
optically-faint and extremely red galaxies at that were previously
missing from galaxy census estimates. The data indicate the existence of
abundant, dusty and post-starburst-like galaxies down to M, below
the sensitivity limit of Spitzer and ALMA. Modeling the NIRCam and HST
photometry of these red sources can result in extreme, high values for both
stellar mass and star formation rate (SFR); however, including 7 MIRI filters
out to 21m results in decreased mass (median 0.6 dex for
logM/M10), and SFR (median 10 for SFR100
M/yr). At , our sample includes a high fraction of little red
dots (LRDs; NIRCam-selected dust-reddened AGN candidates). We significantly
measure older stellar populations in the LRDs out to rest-frame 3m (the
stellar bump) and rule out a dominant contribution from hot dust emission, a
signature of AGN contamination to stellar population measurements. This allows
us to measure their contribution to the cosmic census at , below the
typical detection limits of ALMA (). We find that
these sources, which are overwhelmingly missed by HST and ALMA, could
effectively double the obscured fraction of the star formation rate density at
compared to some estimates, showing that prior to JWST, the obscured
contribution from fainter sources could be underestimated. Finally, we identify
five sources with evidence for Balmer breaks and high stellar masses at
. While spectroscopy is required to determine their nature, we
discuss possible measurement systematics to explore with future data.Comment: submitted to AAS Journals, comments welcome
A review of the changing culture and social context relating to forensic facial depiction of the dead
The recognition of a decedent by a family member is commonplace in forensic investigation and is often employed as identity confirmation. However, it is recognised that misidentification from facial recognition is also common and faces of the dead may be extremely difficult to recognise due to decomposition or external damage, and even immediate post-mortem changes may be significant enough to confuse an observer. The depiction of faces of the dead can be a useful tool for promoting recognition leading to identification and post-mortem facial depiction is described as the interpretation of human remains in order to suggest the living appearance of an individual. This paper provides an historical context relating to the changing view of society to the presentation and publication of post-mortem facial depictions and discusses the current ethical, practical and academic challenges associated with these images
The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar and APOGEE-2 Data
This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey (TDSS) data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey (SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper (MWM), Local Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys
Structural Investigation of Reactive Sputtered Boron Nitride Films
Abstract not availableNA-NOT AVAILABL
Ultrahard Ti-B-N and Hf-B-N Coatings Preparation and Characterization
Abstract not availableNA-NOT AVAILABL
Evidence for Mixed-Phase Nanocrystalline Boron Nitride Films
Abstract not availableNA-NOT AVAILABL
Ulinganishi wa mofolojia na sintaksia baina ya lugha 19 za Kibantu za Afrika Mashariki [A morphosyntactic comparison of 19 East African Bantu languages]
Katika makala hii tumewasilisha matokeo ya utafiti wetu kuhusu lugha 19 za Kibantu za Afrika Mashariki. Tumeonesha kwamba kuna makundi makuu matatu ambayo yanafanana kiasi cha asilimia 70 au zaidi. Makundi haya yanajikuta katika maeneo mbalimbali ya eneo la utafiti wetu. Kuna kundi la kaskazini, la kati, na la kusini. Tumetumia mbinu maalumu ya kulinganisha mofolojia na sintaksia za lugha hizi, ambayo inatumia vigezo 142 kuelezea kiwangochaufananokati yao.Matokeoya utafitihuuyanaonesha kwambakuna tofauti kubwa bainaya lughahizi.Kiwangochaufananobaina lughahizinikatiyaasimilia45(yaaniuhusiano baina Kikuyu na Kisena) na 80 (baina Kiwabo na Kimakhuwa). Ili kufahamu kwamba kuna makundi maalumu miongoni mwa lugha hizi, tumegawanya lugha ambazo ufanano wao ni
chini ya asimilia 70 na zile ambazo ufanano wao ni juu ya asimilia 70. Inawezekana kwamba
uhusiano uliopo kati ya makundi haya unaonyesha uhusiano wao wa kihistoria
- âŠ