14726409
The distribution of water emission in M17SW
We present a 17-point map of the M17SW cloud core in the 110 → 101 transition of ortho-H2O at 557 GHz obtained with Submillimeter Wave Astronomy Satellite. Water emission was detected in 11 of the 17 observed positions. The line widths of the H2O emission vary between 4 and 9 km s-1 and are similar to other emission lines that arise in the M17SW core. A direct comparison is made between the spatial extent of the H2O emission and the 13CO J = 5 → 4 emission; the good agreement suggests that the H2O emission arises in the same warm, dense gas as the 13CO emission. A spectrum of the H218O line was also obtained at the center position of the cloud core, but no emission was detected. We estimate that the average abundance of ortho-H2O relative to H2 within the M17 dense core is approximately 1 × 10-9, 30 times smaller than the average for the Orion core. Toward the H II region/molecular cloud interface in M17SW the ortho-H2O abundance may be about 5 times larger than in the dense core.
14918025
Water abundance in molecular cloud cores
We present Submillimeter Wave Astronomy Satellite (SWAS) observations of the 110 → 101 transition of ortho-H2O at 557 GHz toward 12 molecular cloud cores. The water emission was detected in NGC 7538, ρ Oph A, NGC 2024, CRL 2591, W3, W3OH, Mon R2, and W33 and was not detected in TMC-1, L134N, and B335. We also present a small map of the H2O emission in S140. Observations of the H218O line were obtained toward S140 and NGC 7538, but no emission was detected. The abundance of ortho-H2O relative to H2 in the giant molecular cloud cores was found to vary between 6 × 10-10 and 1 × 10-8. Five of the cloud cores in our sample have previous H2O detections; however, in all cases the emission is thought to arise from hot cores with small angular extents. The H2O abundance estimated for the hot core gas is at least 100 times larger than in the gas probed by SWAS. The most stringent upper limit on the ortho-H2O abundance in dark clouds is provided in TMC-1, where the 3 σ upper limit on the ortho-H2O fractional abundance is 7 × 10-8.
119922132
Transport beam line for ultraslow monoenergetic antiprotons
A beam line for the transportation of slow antiprotons from a multiring electrode trap to an experimental chamber is described. The beam line is equipped with a three-stage differential pumping system in order to maintain a pressure lower than 1×10−12 Torr in the trap region while simultaneously having a pressure of around 1×10−6 Torr in the chamber. Tests have shown that 105 positive ions per trapping cycle were successfully extracted at 250 eV from the trap positioned in a superconducting solenoid. The ions were then further transported through three small apertures to the target area located 3.5 m downstream of the trap. Results from the first delivery of a 250 eV antiproton beam are described.
119266949
MULTIBAND STUDIES OF THE OPTICAL PERIODIC MODULATION IN THE X-RAY BINARY SAX J1808.4–3658 DURING ITS QUIESCENCE AND 2008 OUTBURST
We report on time-resolved optical imaging of the X-ray binary SAX J1808.4-3658 during its quiescent state and 2008 outburst. The binary, containing an accretion-powered millisecond pulsar, has a large sinusoidal-like modulation in its quiescent optical emission. We employ a Markov chain Monte Carlo technique to fit our multi-band light curve data in quiescence with an irradiated star model, and derive a tight constraint of 50(-5)(+6) deg on the inclination angle i of the binary system. The pulsar and its companion are constrained to have masses of 0.97(-0.22)(+0.31) M-circle dot and 0.04(-0.01)(+0.02) M-circle dot (both 1 sigma ranges), respectively. The dependence of these results on the measurements of the companion's projected radial velocity is discussed. We also find that the accretion disk had nearly constant optical fluxes over a similar to 500 day period in the quiescent state our data covered, but started brightening 1.5 months before the 2008 outburst. Variations in modulation during the outburst were detected in our four observations made 7-12 days after the start of the outburst, and a sinusoidal-like modulation with 0.2 mag amplitude changed to have a smaller amplitude of 0.1 mag. The modulation variations are discussed. We estimate the albedo of the companion during its quiescence and the outburst, which was approximately 0 and 0.8 (for isotropic emission), respectively. This large difference probably provides additional evidence that the neutron star in the binary turns on as a radio pulsar in quiescence.
119397253
Evidence for superdeformation in Dy-149,Dy-150: Onset of the collapse of the Z=66 deformed shell closure?
An experiment has been performed to search for superdeformed (SD) states in Dy-149,Dy-150. While no evidence for discrete superdeformed states has been observed, a superdeformed ridge with a separation of Delta E-gamma=52 keV with a total intensity of 1.8+/-0.5% that of Dy-150 has been observed. An upper limit of 0.8% (0.9%), of the intensity of Dy-150 (Dy-149), is placed for observation of the most intense discrete line states. The relative weakness in the SD population is suggested to be due to a rapid decrease in the depth of the superdeformed minimum, as one moves away from doubly magic Dy-152.
119232297
Subaru Constraint on Circular Polarization in I-Band Emission from the Magnetar 4U 0142+61
We present the first imaging circular polarimetry of the anomalous X-ray pulsar (AXP) 4U 0142+61 at optical wavelengths. The AXP is the only magnetar that has been well studied at optical and infrared wavelengths, and is known to have a complicated broad-band spectrum over the wavelength range. The optical polarimetric observation was carried out with the 8.2-m Subaru telescope at the I-band. From the observation, the degree of circular polarization, V, was measured to be V = 1.1 +/- 2.0%, or vertical bar V vertical bar <= 4.3% (90% confidence). The relatively large uncertainty was due to the faintness of the source (I = 23.4-24.0). Considering the currently suggested models for optical emission from magnetars, our result is not sufficiently conclusive to discriminate the models. We suggest that because linear polarization is expected to be strong in the models, linear polarimetry of this magnetar should be conducted.
118394396
Analysis of strong decays of the charmed mesons $D_J(2580), D^*_J(2650), D_J(2740), D^*_J(2760), D_J(3000), D^*_J(3000)$
In this article, we tentatively identify the charmed mesons $D_J(2580)$, $D_J^*(2650)$, $D_J(2740)$, $D^*_J(2760)$, $D_J(3000)$, $D_J^*(3000)$ observed by the LHCb collaboration according to their spin, parity and masses, then study their strong decays to the ground state charmed mesons plus light pseudoscalar mesons with the heavy meson effective theory in the leading order approximation, and obtain explicit expressions of the decay widths. The ratios among the decay widths can be used to confirm or reject the assignments of the newly observed charmed mesons. The strong coupling constants in the decay widths can be fitted to the experimental data in the future at the LHCb, BESIII, KEK-B and $\rm{\bar{P}ANDA}$.
53385594
An intrinsic connection between topological stabilities of Fermi surfaces and topological insulators/superconductors
A topology-intrinsic connection between the stabilities of Fermi surfaces (FSs) and topological insulators/superconductors (TIs/TSCs) is revealed. In particular, a one-to-one relation between the topological types of FSs and TIs/TSCs is rigorously derived; combining it with a well-established topological theory of FSs, we produce a complete table illustrating precisely topological types of all TIs/TSCs, while a valid part of it was postulated before. Moreover, we propose and prove a general index theorem that relates the topological charge of FSs on the natural boundary of a strong TI/TSC to its bulk topological number. Implications of the general index theorem on the boundary quasi-particles are also addressed.
54803118
Analysis of the scalar doubly heavy tetraquark states with QCD sum rules
In this article, we perform a detailed study of the mass spectrum of the scalar doubly charmed and doubly bottom tetraquark states using the QCD sum rules.
16893295
ASCA observations of two SNRs and NEI analysis
Based on the data from the ASCA observation of SNRs Kes79 and W49B, we present here the analysis of their X-ray spectra and morphologies. The Kes79 spectrum can be well fitted by a single NEI component, and the narrow-band images of that source show an inhomogeneous distribution of heavy elements. The heavy elements are richest in the positions S, SE and SW of Kes79, where there may exist interaction between shocks and molecular clouds implied by radio observations. For W49B we present here the non-equilibrium ionization (NEI) analysis based on its emission line diagnostics, and the spectral fit using two NEI components. The reverse shock in W49B may be still hot and we don't find evidence for a hotter blast wave in ASCA spectra.
8434175
X-Ray Observation and Analysis of the Composite Supernova Remnant G327.1–1.1
Based on the data from the observation of the supernova remnant (SNR) G327.1-1.1 by the Advanced Satellite for Cosmology and Astrophysics (ASCA) and ROSAT, we find that G327.1-1.1 is a composite remnant with both a nonthermal emission component and a diffuse thermal emission component. The nonthermal component is well fitted by a power-law model with photon index Γ~2.2. This component is attributed to the emission from the synchrotron nebula powered by an undiscovered central pulsar. The thermal component has a temperature of about 0.4 keV. We attribute it to the emission from the shock-heat swept-up interstellar medium (ISM). Its age, explosion energy, and density of ambient medium are derived from the observed thermal component. Some characteristics of the synchrotron nebula are also derived. We have searched for the pulsed signal but have not found it. The soft X-ray (0.4-2 keV) and hard X-ray (2-10 keV) images are different, but they both elongate in the southeast-northwest direction. And this X-ray southeast-northwest elongation is in positional coincidence with the radio ridge in the Molonglo Observatory Synthesis Telescope (MOST) 843 MHz radio map. We present a possibility that the X-ray nonthermal emission mainly comes from the trail produced by a quickly moving undiscovered pulsar, and the long radio ridge is formed when the pulsar is moving out of the boundary of the plerionic structure.