52 research outputs found
Revisited cold gas content with atomic carbon [C I] in z=2.5 protocluster galaxies
We revisit the cold gas contents of galaxies in a protocluster at z=2.49
using the lowest neutral atomic carbon transition [CI]P-P from
Atacama Large Millimeter/submillimeter Array observations. We aim to test if
the same gas mass calibration applied in field galaxies can be applied to
protocluster galaxies. Five galaxies out of sixteen targeted galaxies are
detected in the [CI] line, and these are all previously detected in CO(3-2) and
CO(4-3) and three in 1.1 mm dust continuum. We investigate the line luminosity
relations between CO and [CI] in the protocluster and compare them with other
previous studies. We then compare the gas mass based on three gas tracers of
[CI], CO(3-2), and dust if at least one of the last two tracers are available.
Using the calibration adopted for field main-sequence galaxies, the [CI]-based
gas measurements are lower than or comparable to the CO-based gas measurements
by -0.35 dex at the lowest with the mean deviation of -0.14 dex. The
differences between [CI]- and the dust- based measurements are relatively mild
by up to 0.16 dex with the mean difference of 0.02 dex. Taking these all
together with calibration uncertainties, with the [CI] line, we reconfirm our
previous findings that the mean gas fraction is comparable to field galaxies
for a stellar-mass range of .
However, at least for these secure five detections, the depletion time scale
decreases more rapidly with stellar mass than field galaxies that might be
related to earlier quenching in dense environments.Comment: accepted for publication in Ap
A Case of Endoscopic Mucosal Resection of Carcinoma in Adenoma at the Minor Duodenal Papilla
Here, we describe a case of minor papillary adenocarcinoma in adenoma that was treated with endoscopic mucosal resection (EMR). In a 67-year-old woman, sigmoid colon cancer was incidentally detected on preoperative upper gastrointestinal endoscopy. Endoscopy revealed a slightly elevated lesion at the minor duodenal papilla. The findings of a histopathologic examination were suggestive of adenocarcinoma. Computed tomography and magnetic resonance images identified a minute tumor, whereas endoscopic ultrasonography revealed that the tumor did not spread to the pancreas. We performed EMR of this lesion. There were no complications, and relapse has not occurred in 3 years. Cases of minor papillary adenocarcinoma treated with EMR are quite rare
X-ray Radiation Damage Effects on Double-SOI Pixel Detectors for the Future Astronomical Satellite "FORCE"
We have been developing the monolithic active pixel detector "XRPIX" onboard
the future X-ray astronomical satellite "FORCE". XRPIX is composed of CMOS
pixel circuits, SiO2 insulator, and Si sensor by utilizing the
silicon-on-insulator (SOI) technology. When the semiconductor detector is
operated in orbit, it suffers from radiation damage due to X-rays emitted from
the celestial objects as well as cosmic rays. From previous studies, positive
charges trapped in the SiO2 insulator are known to cause the degradation of the
detector performance. To improve the radiation hardness, we developed XRPIX
equipped with Double-SOI (D-SOI) structure, introducing an additional silicon
layer in the SiO2 insulator. This structure is aimed at compensating for the
effect of the trapped positive charges. Although the radiation hardness to
cosmic rays of the D-SOI detectors has been evaluated, the radiation effect due
to the X-ray irradiation has not been evaluated. Then, we conduct an X-ray
irradiation experiment using an X-ray generator with a total dose of 10 krad at
the SiO2 insulator, equivalent to 7 years in orbit. As a result of this
experiment, the energy resolution in full-width half maximum for the 5.9 keV
X-ray degrades by 17.8 2.8% and the dark current increases by 89
13%. We also investigate the physical mechanism of the increase in the dark
current due to X-ray irradiation using TCAD simulation. It is found that the
increase in the dark current can be explained by the increase in the interface
state density at the Si/SiO2 interface.Comment: 15 pages, 12 figures, accepted for publication in Journal of
Astronomical Telescopes, Instruments, and System
A Radio-to-millimeter Census of Star-forming Galaxies in Protocluster 4C~23.56 at z = 2.5 : Global and local gas kinematics
We present a study of the gas kinematics of star-forming galaxies associated
with protocluster 4C 23.56 at using resolution CO (4-3) data
taken with ALMA. Eleven H emitters (HAEs) are detected in CO (4-3),
including six HAEs that were previously detected in CO (3-2) at a coarser
angular resolution. The detections in both CO lines are broadly consistent in
the line widths and the redshifts, confirming both detections. With an increase
in the number of spectroscopic redshifts, we confirm that the protocluster is
composed of two merging groups with a total halo mass of , suggesting that the protocluster would evolve into
a Virgo-like cluster (). We compare the CO line widths and
the CO luminosities with galaxies in other (proto)clusters ()
and general fields () from other studies. The 4C23.56
protocluster galaxies have CO line widths and luminosities comparable to other
protocluster galaxies on average. On the other hand, the CO line widths are on
average broader by compared to field galaxies, while the median
CO luminosities are similar. The broader line widths can be attributed to both
effects of unresolved gas-rich mergers and/or compact gas distribution, which
is supported by our limited but decent angular resolution observations and the
size estimate of three galaxies. Based on these results, we argue that gas-rich
mergers may play a role in the retention of the specific angular momentum to a
value similar to that of field populations during cluster assembly, though we
need to verify this with a larger number of samples.Comment: 27 pages, 10 figures, 4 tables, ApJ in pres
Conference Highlights of the 16th International Conference on Human Retrovirology: HTLV and Related Retroviruses, 26–30 June 2013, Montreal, Canada
A Radio-to-mm Census of Star-forming Galaxies in Protocluster 4C23.56 at Z = 2.5:Gas Mass and Its Fraction Revealed with ALMA
We investigate gas contents of star-forming galaxies associated with protocluster 4C23.56 at z = 2.49 by using the redshifted CO (3-2) and 1.1 mm dust continuum with the Atacama Large Millimeter/submillimeter Array. The observations unveil seven CO detections out of 22 targeted Hα emitters (HAEs) and four out of 19 in 1.1 mm dust continuum. They have high stellar mass ({M}\star > 4× {10}10 M ⊙) and exhibit a specific star-formation rate typical of main-sequence star-forming galaxies at z˜ 2.5. Different gas-mass estimators from CO (3-2) and 1.1 mm yield consistent values for simultaneous detections. The gas mass ({M}{gas}) and gas fraction ({f}{gas}) are comparable to those of field galaxies, with {M}{gas}=[0.3,1.8]× {10}11× ({α }{CO}/(4.36× A(Z))) {M}⊙ , where {α }{CO} is the CO-to-H2 conversion factor and A(Z) is the additional correction factor for the metallicity dependence of {α }{CO}, and < {f}{gas}> =0.53+/- 0.07 from CO (3-2). Our measurements place a constraint on the cosmic gas density of high-z protoclusters, indicating that the protocluster is characterized by a gas density higher than that of the general fields by an order of magnitude. We found ρ ({H}2)˜ 5× {10}9 {M}⊙ {{Mpc}}-3 with the CO(3-2) detections. The five ALMA CO detections occur in the region of highest galaxy surface density, where the density positively correlates with global star-forming efficiency (SFE) and stellar mass. Such correlations possibly indicate a critical role of the environment on early galaxy evolution at high-z protoclusters, though future observations are necessary for confirmation
LCA ESTIMATION OF END-MILLING CONDITION DERIVED FROM CATALOG-MINING CONSIDERING HUMAN LEARNING CURVE
ABSTRACT Choosing cutting tools and end-milling conditions depends on expert engineers' knowledge and experience, and often a lengthy process of trial and error is required before they obtain appropriate cutting conditions. We have previously proposed data-mining methods to make decisions about end-milling conditions on the basis of catalog data. We cut hardened die steel JIS SKD61 under three kinds of end-milling conditions: catalog recommended conditions, conditions derived from datamining (mined conditions), and expert engineer conditions. We used LCA to evaluate quantitatively the environmental impact resulting from these conditions. We designed an index model of the environmental burden in the technical mastering process under the three condition. The results show that unskilled engineers could decrease the cumulative environmental burden by working under the mined condition in the initial stage. Recommending the use of the mined condition in the initial stage is therefore considered best
Influence of the SST Rise on Baroclinic Instability Wave Activity under an Aquaplanet Condition
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