Hubrig, S., Stelzer, B., Schoeller, M., Grady, C., Schuetz, O., Pogodin, M. A., ...
Among the 21 Herbig Ae/Be stars studied, new detections of a magnetic field were achieved in six stars. For three Herbig Ae/Be stars, we confirm previous magnetic field detections. The largest...
HD 100453: A Link Between Gas-Rich Protoplanetary Disks and Gas-Poor Debris Disks (2009)
Collins, K. A., Grady, C. A., Hamaguchi, K., Wisniewski, J. P., Brittain, S., Sitko, M., ...
HD 100453 has an IR spectral energy distribution (SED) which can be fit with a power-law plus a blackbody. Previous analysis of the SED suggests that the system is a young Herbig Ae star with a...
3D modelling of the colliding winds in Eta Carinae - evidence for radiative inhibition (2009)
Parkin, E. R., Pittard, J. M., Corcoran, M. F., Hamaguchi, K., Stevens, I. R.
The X-ray emission from the super-massive star Eta Carinae is simulated using a three dimensional model of the wind-wind collision. In the model the intrinsic X-ray emission is spatially extended and...
Physics Interplay of the LHC and the ILC (2008)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2008)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2008)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Henley, D. B., Corcoran, M. F., Pittard, J. M., Stevens, I. R., Hamaguchi, K., Gull, T. R.
We report on variations in important X-ray emission lines in a series of Chandra grating spectra of the supermassive colliding wind binary star Eta Carinae, including key phases around the X-ray...
Supersymmetric Inflation of Dynamical Origin (2008)
Dynamical models of inflation are given with composite inflatons by means of massive supersymmetric gauge theory. Nearly flat directions and stable massive ones in the potential are identified and...
Determining the mass for an ultralight gravitino at LHC (2007)
Hamaguchi, K., Shirai, S., Yanagida, T. T.
In supersymmetric (SUSY) models with the gravitino being the lightest SUSY particle (LSP), the SUSY breaking scale (i.e., the gravitino mass) could be determined by measuring the lifetime of the...
Composite Messenger Baryon as a Cold Dark Matter (2007)
Hamaguchi, K., Shirai, S., Yanagida, T. T.
Among various supersymmetric (SUSY) models, gauge-mediated SUSY breaking models with an ultra-light gravitino of mass m_{3/2} \lesssim O(10) eV are very attractive, since they are completely free...
Determining the Mass for a Light Gravitino (2007)
Hamaguchi, K., Shirai, S., Yanagida, T. T.
Gauge mediated supersymmetry breaking scenarios with an ultra-light gravitino of mass m_{3/2}=1-10 eV are very interesting, since there is no cosmological gravitino problem. We propose a new...
Seesaw Neutrinos from the Heterotic String (2007)
Buchmüller, W, Hamaguchi, K, Lebedev, O, Ramos-Sanchez, S, Ratz, M
We study the possibility of realizing the neutrino seesaw mechanism in the E8XE8 heterotic string. In particular, we consider its Z_6 orbifold compactifications leading to the supersymmetric standard...
Eta Car and Its Surroundings: the X-ray Diagnosis (2007)
Corcoran, M. F., Hamaguchi, K.
X-ray emission from the supermassive star Eta Carinae (\ec) originates from hot shocked gas produced by current stellar mass loss as well as ejecta from prior eruptive events. Absorption of this...
Stau-catalyzed $^6$Li Production in Big-Bang Nucleosynthesis (2007)
Hamaguchi, K., Hatsuda, T., Kamimura, M., Kino, Y., Yanagida, T. T.
If the gravitino mass is in the region from a few GeV to a few 10's GeV, the scalar lepton X such as stau is most likely the next lightest supersymmetry particle. The negatively charged and...
Eta Carinae across the 2003.5 minimum: Spectroscopic Evidence for Massive Binary Interactions (2007)
Nielsen, K. E., Corcoran, M. F., Gull, T. R., Hillier, D. J., Hamaguchi, K., Ivarsson, S., ...
We have analyzed high spatial, moderate spectral resolution observations of Eta Carinae obtained with the STIS from 1998.0 to 2004.3. The spectra show prominent P-Cygni lines in H I, Fe II and He I...
Gravitino Dark Matter in R-Parity Breaking Vacua. (2007)
W. Buchmuller, DESY Forschung Hochenergiephysik, L. Covi, K. Hamaguchi, A. Ibarra, T. Yanagida
Journal article
Seesaw Neutrinos From the Heterotic String. (2007)
W. Buchmuller, DESY Forschung Hochenergiephysik, K. Hamaguchi, O. Lebedev, S. Ramos-Sanchez, M. Ratz
Journal article
The disk and environment of a young Vega analog: HD 169142 (2007)
Grady, C. A., Schneider, G., Hamaguchi, K., Sitko, M. L., Carpenter, W. J., Hines, D., ...
We trace the disk of HD 169142 (A8 Ve) from 0.57" to 1.4" (~80-200 AU projected distance) in 1.1 mum scattered light with HST NICMOS coronagraphy. The azimuthally symmetric disk has a peak...
C. A. Grady, G. Schneider, K. Hamaguchi, M. L. Sitko, W. J. Carpenter, D. Hines, ...
We trace the disk of HD 169142 (A8Ve) from 0.57 ′ ′ to 1.4 ′ ′ (≈80-200 AU projected distance) in 1.1µm scattered light with HST/NICMOS coronagraphy. The azimuthally-symmetric disk has a...
Prospects to study a long-lived charged next lightest supersymmetric particle at the LHC (2006)
Hamaguchi, K, Nojiri, M M, De Roeck, A
If the scalar tau $\stau$ is the next lightest supersymmetric particle and decays into a gravitino ($\gravitino$) being the lightest supersymmetric particle, it will have generally a very long...
Ishisaki, Y., Maeda, Y., Fujimoto, R., Ozaki, M., Ebisawa, K., Takahashi, T., ...
We have developed a framework for the Monte-Carlo simulation of the X-Ray Telescopes (XRT) and the X-ray Imaging Spectrometers (XIS) onboard Suzaku, mainly for the scientific analysis of spatially...
V1647 Ori: The X-ray Evolution of a Pre-main Sequence Accretion Burst (2006)
Kastner, J. H., Richmond, M., Grosso, N., Weintraub, D. A., Simon, T., Henden, A., ...
We present Chandra X-ray Observatory monitoring observations of the recent accretion outburst displayed by the pre-main sequence (pre-MS) star V1647 Ori. The X-ray observations were obtained over a...
Stau-catalyzed Nuclear Fusion (2006)
Hamaguchi, K., Hatsuda, T., Yanagida, T. T.
We point out that the stau may play a role of a catalyst for nuclear fusions if the stau is a long-lived particle as in the scenario of gravitino dark matter. In this letter, we consider d d fusion...
Suzaku Reveals Helium-burning Products in the X-ray Emitting Planetary Nebula BD+303639 (2006)
Murashima, M., Kokubun, M., Makishima, K., Kotoku, J., Murakami, H., Matsushita, K., ...
BD+303639, the brightest planetary nebula at X-ray energies, was observed with Suzaku, an X-ray observatory launched on 2005 July 10. Using the X-ray Imaging Spectrometer, the K-lines from C VI, O...
On the origin of the X-ray emission from Herbig Ae/Be stars (2006)
Stelzer, B., Micela, G., Hamaguchi, K.
We performed a systematic search for Chandra archival observations of Herbig Ae/Be stars. These stars are fully radiative and not expected to support dynamo action analogous to their convective...
Eluding the BBN constraints on the stable gravitino (2006)
Buchmuller, W., Hamaguchi, K., Ibe, M., Yanagida, T. T.
We investigate how late-time entropy production weakens the Big-Bang Nucleosynthesis (BBN) constraints on the gravitino as lightest superparticle with a charged slepton as next-to-lightest...
Physics interplay of the LHC and the ILC. (2006)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e(+)e(-) Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Another Look at LTL Model Checking (2006)
Clarke, E., Grumberg, O., Hamaguchi, K.
We show how LTL model checking can be reduced to CTL model checking with fairness constraints. Using this reduction, we also describe how to construct a symbolic LTL model checker that appears to be...
Moduli/Inflaton Mixing with Supersymmetry Breaking Field. (2006)
M. Endo, DESY Forschung Hochenergiephysik, K. Hamaguchi, F. Takahashi
Journal article
Moduli-Induced Gravitino Problem. (2006)
M. Endo, DESY Forschung Hochenergiephysik, K. Hamaguchi, F. Takahashi
Journal article
The Gravitino in Gaugino Mediation. (2006)
W. Buchmüller, DESY Forschung Hochenergiephysik, K. Hamaguchi, J. Kersten
Journal article
Eluding the BBN Constraints on the Stable Gravitino. (2006)
W. Buchmüller, DESY Forschung Hochenergiephysik, K. Hamaguchi, M. Ibe, T.T. Yanagida
Internal report | Preprint
Supersymmetric Standard Model from the Heterotic String. (2006)
W. Buchmüller, DESY Forschung Hochenergiephysik, K. Hamaguchi, O. Lebedev, M. Ratz
Journal article
Supersymmetric Standard Model from the Heterotic String (II). (2006)
W. Buchmüller, DESY Forschung Hochenergiephysik, K. Hamaguchi, O. Lebedev, M. Ratz
Internal report | Preprint
Eruptive young stellar object in Ldn 1415 (2006)
Kastner, Joel, Richmond, M., Simon, T., Grosso, N., Weintraub, D., Hamaguchi, K.
J. Kastner and M. Richmond, Rochester Institute of Technology; T. Simon, Institute for Astronomy, Honolulu; N. Grosso, Laboratoire d'Astrophysique de Grenoble; D. Weintraub, Vanderbilt University;...
Astronomy Astrophysics manuscript no. 5006 c ESO 2006 (2006)
May On The, B. Stelzer, G. Micela, K. Hamaguchi
Context. Herbig Ae/Be stars are fully radiative and not expected to support dynamo action analogous to their convective lower-mass counterparts, the T Tauri stars. Alternative X-ray production...
Ebisawa, K., Tsujimoto, M., Paizis, A., Hamaguchi, K., Bamba, A., Cutri, R., ...
Using the Chandra Advanced CCD Imaging Spectrometer Imaging array (ACIS-I), we have carried out a deep hard X-ray observation of the Galactic plane region at (l,b) ~ (28.5, 0.0), where no discrete...
Physics Interplay of the LHC and the ILC (2005)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Grosso, N., Kastner, J. H., Ozawa, H., Richmond, M., Simon, T., Weintraub, D. A., ...
We report a ~38 ks X-ray observation of McNeil's Nebula obtained with XMM on 2004 April 4. V1647 Ori, the young star in outburst illuminating McNeil's Nebula, is detected with XMM and appears...
Signatures of Axinos and Gravitinos at Colliders (2005)
Brandenburg, A, Covi, L, Hamaguchi, K, Roszkowski, L, Steffen, F D
The axino and the gravitino are well-motivated candidates for the lightest supersymmetric particle (LSP) and also for cold dark matter in the Universe. Assuming that a charged slepton is the...
Signatures of Axinos and Gravitinos at Colliders (2005)
Brandenburg, A, Covi, L, Hamaguchi, K, Roszkowski, L, Steffen, F D
The axino and the gravitino are well-motivated candidates for the lightest supersymmetric particle (LSP) and also for cold dark matter in the Universe. Assuming that a charged slepton is the...
Signatures of Axinos and Gravitinos at Colliders (2005)
Brandenburg, A., Covi, L., Hamaguchi, K., Roszkowski, L., Steffen, F. D.
The axino and the gravitino are well-motivated candidates for the lightest supersymmetric particle (LSP) and also for cold dark matter in the Universe. Assuming that a charged slepton is the...
Probing lepton flavour violation in slepton NLSP scenarios (2004)
In supersymmetric models where the gravitino is the lightest superparticle, the next-to-lightest superparticle (NLSP) is long-lived, and hence could be collected and studied in detail. We study the...
XMM-Newton Observations of the 2003 X-ray Minimum of Eta Carinae (2004)
Hamaguchi, K., Corcoran, M. F., Gull, T., White, N. E., Damineli, A., Davidson, K.
The XMM-Newton X-ray observatory took part in the multi-wavelength observing campaign of the massive, evolved star Eta Carinae in 2003 during its recent X-ray minimum. This paper reports on the...
X-ray Gyrations of Eta Carinae, or, Is Presence of Evidence Evidence of Presence? (2004)
Corcoran, M. F., Hamaguchi, K., Gull, T., Damineli, A., Davidson, K.
We review the properties of the variable X-ray emission from the extremely massive star Eta Carinae concentrating on the last X-ray minimum, and briefly consider the possible role of a binary...
Physics Interplay of the LHC and the ILC (2004)
Weiglein, Georg, Barklow, T, Boos, E, De Roeck, A, Desch, Klaus, Gianotti, F, ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2004)
Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
A study of late decaying charged particles at future colliders (2004)
Hamaguchi, K, Nojiri, M M, Nakaya, T, Kuno, Y
In models where the gravitino is the lightest supersymmetric particle (LSP), the next-to-lightest supersymmetric particle (NLSP) is long-lived. We consider an important charged NLSP candidate, the...
A study of late decaying charged particles at future colliders (2004)
Hamaguchi, K, Kuno, Y, Nakaya, T, Nojiri, M M
In models where the gravitino is the lightest supersymmetric particle (LSP), the next-to-lightest supersymmetric particle (NLSP) is long-lived. We consider an important charged NLSP candidate, the...
An X-ray Outburst from the Rapidly Accreting Young Star That Illuminates McNeil's Nebula (2004)
Kastner, J. H., Richmond, M., Grosso, N., Weintraub, D. A., Simon, T., Frank, A., ...
Young, low-mass stars are luminous X-ray sources whose powerful X-ray flares may exert a profound influence over the process of planet formation. The origin of such emission is uncertain. Although...
A Chandra Deep X-ray Exposure on the Galactic Plane and Near Infrared Identification (2004)
Ebisawa, K., Paizis, A., Couvoisier, T. J. -L., Dubath, P., Tsujimoto, M., Hamaguchi, K., ...
Using the Chandra ACIS-I instruments, we have carried out a deep X-ray observation on the Galactic plane region at (l,b) ~ (28.5, 0.0), where no discrete X-ray sources have been known previously. We...
Waiting in the Wings: Reflected X-ray Emission from the Homunculus Nebula (2004)
Corcoran, M. F., Hamaguchi, K., Gull, T., Davidson, K., Petre, R., Hillier, D. J., ...
We report the first detection of X-ray emission associated with the Homunculus Nebula which surrounds the supermassive star Eta Carinae. The emission is characterized by a temperature in excess of...
Rho, J., Ramirez, S., Corcoran, M. F., Hamaguchi, K., Lefloch, B.
The Trifid Nebula, a young star-forming HII region, was observed for 16 hours by the Chandra X-ray Observatory. We detected 304 X-ray sources, thirty percent of which are hard sources and seventy...
Physics Interplay of the LHC and the ILC (2004)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2004)
Weiglein, G., Barklow, T., Boos, E., A. De, Roeck, Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2004)
Weiglein, G., Barklow, T., Boos, E., A. De, Roeck, Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Physics Interplay of the LHC and the ILC (2004)
Weiglein, G., Barklow, T., Boos, E., De Roeck, A., Desch, K., Gianotti, F., ...
Physics at the Large Hadron Collider (LHC) and the International e+e- Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and...
Gauge Couplings at High Temperature and the Relic Gravitino Abundance (2003)
Buchmüller, W., Hamaguchi, K., Ratz, M.
In higher-dimensional supersymmetric theories gauge couplings of the effective four-dimensional theory are determined by expectation values of scalar fields. We find that at temperatures above a...
Nonanomalous Discrete R-Symmetry and Light Gravitino (2003)
We discuss nonanomalous R-symmetry in the supersymmetric grand unified theories. In particular, we explore anomaly-free solutions predicting the gravitino mass in the range of $10^{-3} eV \lsim...
Nonanomalous Discrete R-Symmetry and Light Gravitino (2003)
We discuss nonanomalous R-symmetry in the supersymmetric grand unified theories. In particular, we explore anomaly-free solutions predicting the gravitino mass in the range of $10^{-3} eV \lsim...
Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage multi-user detection (MUD) scheme designed for a fast-FH/MFSK system is proposed, in which the received signal level is attenuated by a constant scaling factor when the signal is deemed...
Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage multi-user detection (MUD) scheme designed for a fast-FH/MFSK system is proposed, in which the received signal level is attenuated by a constant scaling factor when the signal is deemed...
Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage multi-user detection (MUD) scheme designed for a fast-FH/MFSK system is proposed, in which the received signal level is attenuated by a constant scaling factor when the signal is deemed...
On the performance of Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage Multi-User Detection (MUD) scheme designed for a fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) system is proposed, which exploits the explicit knowledge of the...
Time-Frequency Spread OFDM/FHMA (2003)
A combined scheme based on Orthogonal Frequency-Division Multiplexing and Frequency-Hopped Multiple Access (OFDM/FHMA) is proposed, in which the transmitted data is spread over both the time and...
Multi-Stage Multi-User Detection Assisted Asynchronous Fast-FH/MFSK (2003)
A multi-stage Multi-User Detection (MUD) scheme designed for asynchronous fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) systems is proposed, in which each signal detection...
On the performance of Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage Multi-User Detection (MUD) scheme designed for a fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) system is proposed, which exploits the explicit knowledge of the...
Time-Frequency Spread OFDM/FHMA (2003)
A combined scheme based on Orthogonal Frequency-Division Multiplexing and Frequency-Hopped Multiple Access (OFDM/FHMA) is proposed, in which the transmitted data is spread over both the time and...
Multi-Stage Multi-User Detection Assisted Asynchronous Fast-FH/MFSK (2003)
A multi-stage Multi-User Detection (MUD) scheme designed for asynchronous fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) systems is proposed, in which each signal detection...
On the performance of Multi-Stage Multi-User Detection Assisted Fast-FH/MFSK (2003)
Hamaguchi, K., Yang, L-L., Hanzo, L.
A multi-stage Multi-User Detection (MUD) scheme designed for a fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) system is proposed, which exploits the explicit knowledge of the...
Time-Frequency Spread OFDM/FHMA (2003)
A combined scheme based on Orthogonal Frequency-Division Multiplexing and Frequency-Hopped Multiple Access (OFDM/FHMA) is proposed, in which the transmitted data is spread over both the time and...
Multi-Stage Multi-User Detection Assisted Asynchronous Fast-FH/MFSK (2003)
A multi-stage Multi-User Detection (MUD) scheme designed for asynchronous fast Frequency-Hopping/Multilevel Frequency-Shift-Keying (fast-FH/MFSK) systems is proposed, in which each signal detection...
Leptogenesis in supersymmetric model is discussed comprehensively and in detail. In the first half, we discuss several leptogenesis mechanisms by the decay of heavy right-handed neutrino, which...
Leptogenesis in supersymmetric model is discussed comprehensively and in detail. In the first half, we discuss several leptogenesis mechanisms by the decay of heavy right-handed neutrino, which...
Democratic (S)fermions and Lepton Flavor Violation (2002)
Hamaguchi, K., Kakizaki, Mitsuru, Yamaguchi, Masahiro
The democratic approach to account for fermion masses and mixing is known to be successful not only in the quark sector but also in the lepton sector. Here we extend this ansatz to supersymmetric...
Non-thermal Dark Matter from Affleck-Dine Baryogenesis (2002)
In this talk we discuss the origin and nature of the dark matter in the Affleck-Dine (AD) baryogenesis. The AD baryogenesis via most of the flat directions predict formations of large Q-balls, and a...
Non-thermal dark matter via Affleck-Dine baryogenesis and its detection possibility (2002)
The formation and late time decays of Q-balls are generic consequences of the Affleck-Dine (AD) baryogenesis. A substantial amount of the lightest supersymmetry (SUSY) particles (LSP's) are produced...
Non-thermal dark matter via Affleck-Dine baryogenesis and its detection possibility (2002)
The formation and late time decays of Q-balls are generic consequences of the Affleck-Dine (AD) baryogenesis. A substantial amount of the lightest supersymmetry (SUSY) particles (LSPs) are produced...
Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
If the baryon asymmetry in the present universe is generated by decays of the $L H_u$ flat direction, the observed baryon asymmetry requires the mass of the lightest neutrino to be much smaller than...
Leptogenesis with Almost Degenerate Majorana Neutrinos (2002)
Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
We investigate the leptogenesis with almost degenerate neutrinos, in the framework of democratic mass matrix, which naturally explains the large mixing angles for neutrino oscillations as well as...
Chandra Observations of High Mass Young Stellar Objects in the Monoceros R2 molecular cloud (2001)
Kohno, M., Koyama, K., Hamaguchi, K.
We observed the Monoceros R2 molecular cloud with the ACIS-I array onboard the Chandra X-ray Observatory. From the central 3.2' x 3.2' region, we detect 154 sources above the detection limit of...
Higgsino and Wino Dark Matter from Q-ball Decay in Affleck-Dine Baryogenesis (2001)
We claim that the Higgsino-like and wino-like neutralinos can be good dark matter candidates if they are produced by the late time decay of Q-ball, which is generally formed in Affleck-Dine...
Leptogenesis via $LH_{u}$ flat direction with a gauged $U(1)_{B-L}$ (2001)
Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
We study the supersymmetric leptogenesis via $LH_{u}$ flat direction with a gauged $U(1)_{B-L}$ symmetry. We find that the resultant baryon asymmetry is enhanced compared with the case without a...
Leptogenesis from $\widetilde{N}$-dominated early universe (2001)
Hamaguchi, K., Murayama, Hitoshi, Yanagida, T.
We investigate in detail the leptogenesis by the decay of coherent right-handed sneutrino $\widetilde{N}$ having dominated the energy density of the early universe, which was originally proposed by...
Cosmological Constraint on the Zee model (2001)
Haba, N., Hamaguchi, K., Suzuki, Tomoharu
It is well known that the Zee model induces small neutrino masses by radiative corrections, where the bi-maximal flavor mixing is possible. We analyze the cosmological condition in order for the...
Affleck-Dine baryo/leptogenesis with a gauged U(1)(B-L) (2001)
Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
We briefly review the present status of Affleck-Dine baryo/leptogenesis scenarios in the minimal supersymmetric standard model (MSSM) in the context of the gravity-mediated SUSY breaking, and show...
Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
In this paper we point out that the cosmological baryon asymmetry in our universe is generated almost independently of the reheating temperature $T_R$ in Affleck-Dine leptogenesis and it is...
Variations on Supersymmetry Breaking and Neutrino Spectra (2000)
Borzumati, F., Hamaguchi, K., Nomura, Y., Yanagida, T.
The problem of generating light neutrinos within supersymmetric models is discussed. It is shown that the hierarchy of scales induced by supersymmetry breaking can give rise to suppression factors of...
Supersymmetric seesaw model for the (1+3)-scheme of neutrino masses (2000)
Borzumati, F., Hamaguchi, K., Yanagida, T.
A four-neutrino spectrum with a sterile neutrino without significant involvement in the atmospheric and solar neutrino oscillation experiments has been recently advocated as the correct picture to...
Affleck-Dine Leptogenesis with an Ultralight Neutrino (2000)
Asaka, T., Fujii, Masaaki, Hamaguchi, K., Yanagida, T.
We perform a detailed analysis on Affleck-Dine leptogenesis taking into account the thermal effects on the dynamics of the flat direction field $\phi$. We find that an extremely small mass for the...
Cosmological Gravitino Problem in Gauge-Mediated Supersymmetry Breaking Models (2000)
Asaka, T., Hamaguchi, K., Suzuki, Koshiro
We investigate the cosmological gravitino problem in gauge-mediated supersymmetry breaking models, where the gravitino becomes in general the lightest supersymmetric particle (LSP). In order to avoid...
Variations on Supersymmetry Breaking and Neutrino Spectra (2000)
Borzumati, Francesca, Hamaguchi, K., Nomura, Y., Yanagida, T.
X-ray Flare from a Herbig Be star, MWC297 (1999)
Hamaguchi, K., Terada, H., Bamba, A., Koyama, K.
Hard X-ray emissions from a Herbig Be star MWC297 were discovered in three separate observations spanning 5 days in April 1994 with the Advanced Satellite for Cosmology and Astrophysics (ASCA). An...
Leptogenesis in Inflationary Universe (1999)
Asaka, T., Hamaguchi, K., Kawasaki, M., Yanagida, T.
We investigate the leptogenesis via decays of heavy Majorana neutrinos which are produced non-thermally in inflaton decays. We make a comprehensive study on the leptogenesis assuming various...
Leptogenesis in Inflaton Decay (1999)
Asaka, T., Hamaguchi, K., Kawasaki, M., Yanagida, T.
We study a leptogenesis via decays of heavy Majorana neutrinos produced non-thermally in inflaton decays. We find that this scenario is fully consistent with existing supersymmetric inflation models...
Long-Lived Superheavy Particles in Dynamical Supersymmetry-Breaking Models in Supergravity (1999)
Hamaguchi, K., Nomura, Yasunori, Yanagida, T.
Superheavy particles of masses $\simeq 10^{13}-10^{14} GeV$ with lifetimes $\simeq 10^{10}-10^{22} years$ are very interesting, since their decays may account for the ultra-high energy (UHE) cosmic...
Long Lived Superheavy Dark Matter with Discrete Gauge Symmetries (1998)
Hamaguchi, K., Nomura, Yasunori, Yanagida, T.
The recently observed ultra-high energy (UHE) cosmic rays beyond the Greisen-Zatsepin-Kuzmin bound can be explained by the decays of some superheavy $X$ particles forming a part of dark matter in our...
Superheavy Dark Matter with Discrete Gauge Symmetries (1998)
Hamaguchi, K., Nomura, Yasunori, Yanagida, T.
We show that there are discrete gauge symmetries protect naturally heavy X particles from decaying into the ordinary light particles in the supersymmetric standard model. This makes the proposal very...
Effectiveness of a Ligating Device for Endoscopic Surgery (1995)
T. Hachisu, H. Yamada, K. Hamaguchi
A new detachable snare for hemostasis in the removal of large polyps or other elevated lesion was developed by the author (Olympus Ligating Device). It allows ligation to be performed through the...
Another Look at LTL Model Checking (1994)
E. Clarke, O. Grumberg, K. Hamaguchi
We show how LTL model checking can be reduced to CTL model checking with fairness constraints. Using this reduction, we also describe how to construct a symbolic LTL model checker that appears to be...
Another Look at LTL Model Checking (1994)
E. Clarke, O. Grumberg, K. Hamaguchi
We show how LTL model checking can be reduced to CTL model checking with fairness constraints. Using this reduction, we also describe how to construct a symbolic LTL model checker that appears to be...
Study of Lupus Nephritis in Males (1991)
TATENO, S, HIKI, Y, HAMAGUCHI, K, TSUCHIDA, H, SHIGEMATSU, H, KOBAYASHI, Y
Clinical and pathological findings were studied in 23 male patients with lupus nephritis who were followed up for a period of 41±36 months after renal biopsy. Age at renal biopsy was 31±14 years...
Gaskins, H R, Prochazka, M, Hamaguchi, K, Serreze, D V, Leiter, E H
Endogeneous retroviral expression in beta cells is a feature of prediabetes in nonobese diabetic (NOD) mice. The purpose of this study was to characterize the class-specific pattern of retroviral...
Gaskins, H R, Prochazka, M, Hamaguchi, K, Serreze, D V, Leiter, E H
Endogeneous retroviral expression in beta cells is a feature of prediabetes in nonobese diabetic (NOD) mice. The purpose of this study was to characterize the class-specific pattern of retroviral...
Stability of ribonuclease T2 from Aspergillus oryzae.
The stability of ribonuclease T2 (RNase T2) from Aspergillus oryzae against guanidine hydrochloride and heat was studied by using CD and fluorescence. RNase T2 unfolded and refolded reversibly...
Miyake, A., Yamamoto, H., Kubota, E., Hamaguchi, K., Kouda, A., Honda, K., ...
1. YM-26734 [4-(3,5-didodecanoyl-2,4,6-trihydroxyphenyl)-7-hydroxy-2-(4-hydroxyph eny l) chroman] dose-dependently inhibited the activities of extracellular phospholipase A2 (PLA2): rabbit...
A case of Machado-Joseph disease presenting with spastic paraparesis.
Kaneko, A, Narabayashi, Y, Itokawa, K, Nakazato, Y, Hosokawa, T, Iwasaki, S, ...
Effectiveness of a Ligating Device for Endoscopic Surgery
Hachisu, T., Yamada, H., Hamaguchi, K.
A new detachable snare for hemostasis in the removal of large polyps or other elevated lesion was developed by the author (Olympus Ligating Device). It allows ligation to be performed through the...