51 research outputs found
Electronic and Magnetic Phase Diagram of a Superconductor, SmFeAsO1-xFx
A crystallographic and magnetic phase diagram of SmFeAsO1-xFx is determined
as a function of x in terms of temperature based on electrical transport and
magnetization, synchrotron powder x-ray diffraction, 57Fe Mossbauer spectra
(MS), and 149Sm nuclear resonant forward scattering (NRFS) measurements. MS
revealed that the magnetic moments of Fe were aligned antiferromagnetically at
~144 K (TN(Fe)). The magnetic moment of Fe (MFe) is estimated to be 0.34
myuB/Fe at 4.2 K for undoped SmFeAsO; MFe is quenched in superconducting
F-doped SmFeAsO. 149Sm NRFS spectra revealed that the magnetic moments of Sm
start to order antiferromagnetically at 5.6 K (undoped) and 4.4 K (TN(Sm)) (x =
0.069). Results clearly indicate that the antiferromagnetic Sm sublattice
coexists with the superconducting phase in SmFeAsO1-xFx below TN(Sm), while
antiferromagnetic Fe sublattice does not coexist with the superconducting
phase.Comment: Accepted in New Journal of Physic
Absolute X-ray energy measurement using a high-accuracy angle encoder
This paper presents an absolute X-ray photon energy measurement method that uses a Bond diffractometer. The proposed system enables the prompt and rapid in situ measurement of photon energies over a wide energy range. The diffractometer uses a reference silicon single-crystal plate and a highly accurate angle encoder called SelfA. The performance of the system is evaluated by repeatedly measuring the energy of the first excited state of the potassium-40 nuclide. The excitation energy is determined as 29829.39 (6) eV, and this is one order of magnitude more accurate than the previous measurement. The estimated uncertainty of the photon energy measurement was 0.7 p.p.m. as a standard deviation and the maximum observed deviation was 2 p.p.m
D-brane Charges in Gravitational Duals of 2+1 Dimensional Gauge Theories and Duality Cascades
We perform a systematic analysis of the D-brane charges associated with
string theory realizations of d=3 gauge theories, focusing on the examples of
the N=4 supersymmetric U(N)xU(N+M) Yang-Mills theory and the N=3 supersymmetric
U(N)xU(N+M) Yang-Mills-Chern-Simons theory. We use both the brane construction
of these theories and their dual string theory backgrounds in the supergravity
approximation. In the N=4 case we generalize the previously known gravitational
duals to arbitrary values of the gauge couplings, and present a precise mapping
between the gravity and field theory parameters. In the N=3 case, which (for
some values of N and M) flows to an N=6 supersymmetric Chern-Simons-matter
theory in the IR, we argue that the careful analysis of the charges leads to a
shift in the value of the B-field in the IR solution by 1/2, in units where its
periodicity is one, compared to previous claims. We also suggest that the N=3
theories may exhibit, for some values of N and M, duality cascades similar to
those of the Klebanov-Strassler theory.Comment: 47 pages, 9 figures; minor changes, references adde
Branes and fluxes in special holonomy manifolds and cascading field theories
We conduct a study of holographic RG flows whose UV is a theory in 2+1
dimensions decoupled from gravity, and the IR is the N=6,8 superconformal fixed
point of ABJM. The solutions we consider are constructed by warping the
M-theory background whose eight spatial dimensions are manifolds of special
holonomies sp(1) times sp(1) and spin(7). Our main example for the spin(7)
holonomy manifold is the A8 geometry originally constructed by Cvetic, Gibbons,
Lu, and Pope. On the gravity side, our constructions generalize the earlier
construction of RG flow where the UV was N=3 Yang-Mills-Chern-Simons matter
system and are simpler in a number of ways. Through careful consideration of
Page, Maxwell, and brane charges, we identify the discrete and continuous
parameters characterizing each system. We then determine the range of the
discrete data, corresponding to the flux/rank for which the supersymmetry is
unbroken, and estimate the dynamical supersymmetry breaking scale as a function
of these data. We then point out the similarity between the physics of
supersymmetry breaking between our system and the system considered by
Maldacena and Nastase. We also describe the condition for unbroken
supersymmetry on class of construction based on a different class of spin(7)
manifolds known as B8 spaces whose IR is different from that of ABJM and
exhibit some interesting features.Comment: 51 pages, 12 figures. Update in quantization of G4 on B8 in equations
(5.12) and (5.13
Bortezomib-cyclophosphamide-dexamethasone induction/consolidation and bortezomib maintenance for transplant-eligible newly diagnosed multiple myeloma: phase 2 multicenter trial
[Objectives:] We conducted a phase II trial to prospectively evaluate the efficacy and safety of bortezomib-cyclophosphamide-dexamethasone (VCD) induction, autologous stem cell transplantation (ASCT), VCD consolidation, and bortezomib maintenance in transplant-eligible newly diagnosed multiple myeloma (NDMM) patients in Japan (UMIN000010542). [Methods:] From 2013 to 2016, 42 patients with a median age of 58 (range 42–65) years with NDMM were enrolled in 15 centers. The primary endpoint was the complete response (CR) /stringent CR (sCR) rate after transplantation, and overall/progression-free survival rates were also evaluated. [Results:] Following induction therapy, the overall response rate was obtained in 71% of patients, including a CR/sCR of 10% and a very good partial response (VGPR) of 26%. Twenty-six of the 42 patients completed ASCT following the protocol and CR/sCR and VGPR rate 100 days after ASCT was 26% and 17%, respectively. During consolidation therapy, 3 of the 24 patients achieved deeper responses. Eight of the 18 patients completed 2-year bortezomib maintenance without disease progression and grade 3/4 toxicities. Five patients were VGPR or partial response after ASCT but maintained response with 2-year bortezomib maintenance. Two-year overall and progression-free survival rates were 92.5% (95% confidence interval [CI]: 78.5%−97.5%) and 62.6% (95% CI: 45.8%−75.5%), respectively. Grade 3/4 toxicities (≥ 10%) included neutropenia (19%) and anemia (17%) in induction, and thrombocytopenia (29%) in consolidation. [Conclusion:] VCD induction/consolidation and bortezomib maintenance with ASCT for NDMM resulted in a high CR/sCR rate and provided good overall/progression-free survival in Japan
Slow Processes in Supercooled o-Terphenyl: Relaxation and Decoupling
過冷却液体中のミクロなスケールでの固体的振る舞いの観測に成功 -液体状態の基礎理解とガラス転移の解明に期待-. 京都大学プレスリリース. 2012-09-15.We mapped the relaxation times of inter- and intramolecular correlations in o-terphenyl by a quasielastic scattering method using nuclear resonant scattering of synchrotron radiation. From the obtained map, we found that the slow β process is decoupled from the α process at 278 K, and this temperature is clearly below the previous decoupling temperature of 290 K, at which the α-relaxation dynamics changes. Then, it was also concluded that sufficient solidlike condition achieved by further cooling from 290 K is required to decouple the slow β process from the α process and, due to the difference of the length scales between the α and the slow β processes, these two averaged relaxation times are concluded not to cross as an extrapolation assumed so far. Furthermore, evidence of the restricted dynamics of the slow β process could be obtained as an anomalous momentum transfer (q) dependence of ( ∝ q-2.9) at 265 K, observed at q values of 18–48 nm-1
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