236 research outputs found
Metal Abundances in the Hot Interstellar Medium in Early-Type Galaxies Observed with ASCA
We have analyzed ASCA data of 27 early-type galaxies, and studied the
properties of their X-ray emitting ISM (Inter Stellar
Medium) in detail. We found that overlapping lines and free-bound continuum
cause strong coupling in the derived abundances of various elements. The
abundance determination is also difficult due to the uncertainties in the Fe-L
atomic physics, because Fe-L lines couple with O and Ne K-lines. However, when
abundances of -elements are fixed, all the plasma codes give similar Fe
abundances with a scattering of only 20-30%. To relax the strong coupling among
the elements, we included 20% systematic errors in the Fe-L region of the
spectra. Then, in X-ray luminous galaxies, the derived abundance of Fe and
-elements both became solar within a factor of 2. This result
relaxes the previous severe discrepancy between the ISM and stellar
metallicities. The ISM metallicity in X-ray fainter galaxies is still
uncertain, but we can at least constrain that contribution from type-Ia SN to
the ISM abundance is lower than in X-ray luminous systems. These results
strongly suggest that a large fraction of SN Ia products have escaped into
intergalactic space.Comment: 48 pages with 20 figures, Latex(PASJadd.sty, PASJ95.sty), accepted
for publication in PAS
原発性副甲状腺機能亢進症, 尿管ポリープおよび腎盂結石を伴ったKlinefelter症候群の1例
副甲状腺機能亢進症, 右尿管ポリープ, および右腎盂結石を合併したKlinefelter症候群の1例を経験し, その臨床経過を報告するとともに文献的考察を加えた。〔症例〕 55歳男性で右側腹部痛を主訴として来院した。理学的所見で外陰部は男性型であるが発育不良で両側睾丸は小さくeunuchoidal habitusを呈した。既往歴に右尿管結石で5回自然排石が認められたほかに, 16年前gynecomastiaのためmastectomyを受けた事がある。身長171 cm, arm span 177.8 cmで体毛は少なく染色体検査は47XXYでKlinefelter症候群と診断した。血清LH, FSHは高値でテストステロン値は低値を示した。排泄性腎盂造影で右水腎症と右腎孟結石が認められ, 逆行性腎盂造影により右尿管上部に水腎症の原因となる腫瘍による多発性陰影欠損がみられ, 尿細胞診も悪性腫瘍を疑わせたため, 右腎尿管全摘術を施行した。尿管腫瘍は組織学的には多発性の尿管ポリープであった。血清Ca, Pは正常範囲内であるがhypercalciuriaがみられ, %TRPも54%と低値で副甲状腺ホルモン値も高いため, 原発性副甲状腺機能亢進症を疑いcervical explorationを施行した。副甲状腺は, diffuse hyperplasiaを呈し3/4副甲状腺亜全摘術と胸腺摘出術を行った。摘出した胸腺内には異所性副甲状腺組織は認められなかった。文献的に本症候群には糖尿病, 甲状腺機能不全, 下垂体牲腺機能不全などのいくつかの内分泌機能障害が報告されている。しかし本症候群に副甲状腺機能充進を合併した報告は過去に1例をみるにすぎない。副甲状腺機能亢進症の診断上, %TRPと静脈カテーテルによる頸部静脈血のmultiple samplingによる副甲状腺ホルモン測定の意義について言及した。Herein is reported a case of 47 XXV-Klinefelter's syndrome associated with ureteral polyps, renal pelvic stone and primary hyperparathyroidism. To the best of our knowledge, this is the second patient reported to have Klinefelter's syndrome coexisting with primary hyperparathyroidism. Frequent endocrinological disorders in the patients with Klinefelter's syndrome and diagnostic problems for hyperparathyroidism and ureteral polyps are discussed
Detection of Excess Hard X-ray Emission from the Group of Galaxies HCG62
From the group of galaxies HCG62, we detected an excess hard X-ray emission
in energies above keV with \A SCA. The excess emission is spatially
extended up to from the group center, and somewhat enhanced toward
north. Its spectrum can be represented by either a power-law of photon index
0.8-2.7, or a Bremsstrahlung of temperature keV. In the 2-10 keV range,
the observed hard X-ray flux, erg cm
s, implies a luminosity of erg s for a
Hubble constant of 50 km s Mpc. The emission is thus too luminous
to be attributed to X-ray binaries in the memb er galaxies. We discuss possible
origin of the hard X-ray emission.Comment: 6 pages, 3 Postscript figures, uses emulateapj.sty. Accepted for
publication in the Astrophysical Journal Letter
Suzaku Observation of the Metallicity in the Interstellar Medium of NGC 4258
The Suzaku X-ray satellite observed the nearby spiral galaxy NGC 4258 for a
total good exposure time of 100 ks. We present an analysis of the Suzaku XIS
data, in which we confirm that the 0.5--2 keV spectra of the interstellar
medium (ISM) are well-represented by a two-temperature model. The cool and hot
ISM temperatures are 0.23+-0.02 and 0.59 +-0.01 keV, respectively. Suzaku's
excellent spectral sensitivity enables us to measure the metal abundances of O,
Ne, Mg, Si and Fe of the ISM for the first time. The resultant abundance
pattern of O, Mg, Si, and Fe is consistent with that of the new solar abundance
table of Lodders (2003), rather than Anders & Grevesse (1989). This suggests
that the metal enrichment processes of NGC 4258 and of our Galaxy are similar.Comment: 9 pages, 4 figure
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