OHS: OH-airglow Suppressor for the Subaru Telescope

This paper describes an OH-airglow Suppressor (OHS) for the infrared Nasmyth focus of the Subaru telescope. OHS has the capability of eliminating 224 airglow-lines in the $J$- and $H$-bands, which are major sources of background radiation at near-infrared wavelengths up to 2 $\mu$m. Specifically, it is a pre-optics system installed between the telescope and an infrared camera/spectrograph (CISCO). The suppressor reduces sky background emissions to 1/25 and its throughput is 40%. As a result, the S/N gain achieved with OHS is more than 1 mag compared to the typical spectroscopic approach. The limiting magnitude measured during a test observing run was found to be $H$ = 21.1 mag ($\lambda/\Delta\lambda$ = 210, S/N = 5) in the standard 4000 s exposure sequence.Comment: 6 pages, 9 figures. Accepted for publication in PASJ(2001

JHK Spectra of the z=2.39 Radio Galaxy 53W002

We present low-resolution, near-IR JHK spectra of the weak z=2.39 radio galaxy 53W002, obtained with the OH-airglow Suppressor spectrograph (OHS) and Cooled Infrared Spectrograph and Camera for OHS (CISCO) on the Subaru Telescope. They cover rest-frame wavelengths of 3400-7200 A, and the emission lines of [O II]3727, Hb, [O III]4959, 5007, Ha, [N II]6548, 6583 and [S II]6716, 6731 were detected. Using the Ha/Hb line ratio, we find an extinction of E(B-V)=0.14. The emission-line ratios are reproduced by a cloud of electron density n_e=1x10^{3-4}(/cm3) with solar metallicity, ionized by an alpha=-0.7 power-law continuum with ionizing parameter U=1x10^-3. In addition to these emission lines, we make the first spectroscopic confirmation of the Balmer discontinuity in a high-z radio galaxy. Together with rest-frame UV photometry from the literature, we show that at least 1/3 of the present stellar mass was formed in the current starburst. The stellar mass was estimated to be (1-1.4)x10^11 M_sol by one-component model fitting, which is smaller than that of typical z~1 B2/6C radio galaxies. We suggest that 53W002 is currently assembling a large part of its stellar mass through merger events with the surrounding sub-galactic clumps, some of which can be identified with the Lya emitters detected in narrow-band imaging. After a few such events over the next few Gyr, 53W002 will evolve into a massive elliptical galaxy.Comment: 10 pages, including 11 figures. Accepted for publication in PASJ(2001). Revised 5/15/200

Infrared Imaging of the Gravitational Lens PG 1115+080 with the Subaru Telescope

We present high spatial resolution images of the gravitational-lens system PG 1115+080 taken with the near-infrared camera (CISCO) on the Subaru telescope. The FWHM of the combined image is $0.''32$ in the $K'$-band, yielding spatial resolution of $0.''14$ after a deconvolution procedure. This is a first detection of an extended emission adjacent to the A1/A2 components, indicating the presence of a fairly bright emission region with a characteristic angular radius of $\sim$ 5 mas (40 pc). The near-infrared image of the Einstein ring was extracted in both the $J$ and $K'$ bands. The $J-K'$ color is found to be significantly redder than that of a synthetic model galaxy with an age of 3 Gyr, the age of the universe at the quasar redshift.Comment: 11 pages, 6 figures. Accepted for publication in PASJ(2000

[OII]3727 Emission from the Companion to the Quasar BR 1202-0725 at z=4.7

Results of a narrow-band imaging for the redshifted [OII]3727 emission around a quasar at z=4.7 obtained with the Subaru telescope and CISCO (a Cassegrain near infrared camera) are presented. A significant emission line is detected in the narrow-band H_2 (v=1-0 S(1)) filter at a location 2.4" northwest from the quasar, where the presence of a companion has been reported in Lyman alpha emission and the rest-frame UV continuum. We identify this line as [OII]3727 emission and confirm that the source really is a companion at z=4.7. The [OII]3727 flux from the companion is estimated to be 2.5 x 10^{-17} erg s^{-1} cm^{-2}. If the companion is a star forming object, the inferred star formation rate is as high as 45-230 M_{solar} yr^{-1} even without assuming the extinction correction. This value is higher than those derived from the Lyman alpha emission or from the UV continuum. Thus, provided that the difference is caused by dust extinction, the extinction corrected star formation rate is calculated to be 45 to 2300 M_{solar} yr^{-1} depending on the assuming extinction curves.Comment: 15 pages including 3 figures. Accepted for publication in PAS

Stochastic Hamiltonian for Non-Critical String Field Theories from Double-Scaled Matrix Models

We present detailed discussions on the stochastic Hamiltonians for non-critical string field theories on the basis of matrix models. Beginning from the simplest $c=0$ case, we derive the explicit forms of the Hamiltonians for the higher critical case $k=3$ (which corresponds to $c=-22/5$) and for the case $c=1/2$, directly from the double-scaled matrix models. In particular, for the two-matrix case, we do not put any restrictions on the spin configurations of the string fields. The properties of the resulting infinite algebras of Schwinger-Dyson operators associated with the Hamiltonians and the derivation of the Virasoro and $W_3$ algebras therefrom are also investigated. Our results suggest certain universal structure of the stochastic Hamiltonians, which might be useful for an attempt towards a background independent string field theory.Comment: 70 pages, LaTeX, typographical errors are corrected, to be published in Phys. Rev.

A formulation of the Yang-Mills theory as a deformation of a topological field theory based on background field method and quark confinement problem

By making use of the background field method, we derive a novel reformulation of the Yang-Mills theory which was proposed recently by the author to derive quark confinement in QCD. This reformulation identifies the Yang-Mills theory with a deformation of a topological quantum field theory. The relevant background is given by the topologically non-trivial field configuration, especially, the topological soliton which can be identified with the magnetic monopole current in four dimensions. We argue that the gauge fixing term becomes dynamical and that the gluon mass generation takes place by a spontaneous breakdown of the hidden supersymmetry caused by the dimensional reduction. We also propose a numerical simulation to confirm the validity of the scheme we have proposed. Finally we point out that the gauge fixing part may have a geometric meaning from the viewpoint of global topology where the magnetic monopole solution represents the critical point of a Morse function in the space of field configurations.Comment: 45 pages, 3 figures included in LaTe

Universal renormalization-group dynamics at the onset of chaos in logistic maps and nonextensive statistical mechanics

We uncover the dynamics at the chaos threshold $\mu_{\infty}$ of the logistic map and find it consists of trajectories made of intertwined power laws that reproduce the entire period-doubling cascade that occurs for $\mu <\mu_{\infty}$. We corroborate this structure analytically via the Feigenbaum renormalization group (RG) transformation and find that the sensitivity to initial conditions has precisely the form of a $q$-exponential, of which we determine the $q$-index and the $q$-generalized Lyapunov coefficient $\lambda _{q}$. Our results are an unequivocal validation of the applicability of the non-extensive generalization of Boltzmann-Gibbs (BG) statistical mechanics to critical points of nonlinear maps.Comment: Revtex, 3 figures. Updated references and some general presentation improvements. To appear published as a Rapid communication of PR

Reanalysis of the GALLEX solar neutrino flux and source experiments

After the completion of the gallium solar neutrino experiments at the Laboratori Nazionali del Gran Sasso (GALLEX}: 1991-1997; GNO: 1998-2003) we have retrospectively updated the GALLEX results with the help of new technical data that were impossible to acquire for principle reasons before the completion of the low rate measurement phase (that is, before the end of the GNO solar runs). Subsequent high rate experiments have allowed the calibration of absolute internal counter efficiencies and of an advanced pulse shape analysis for counter background discrimination. The updated overall result for GALLEX (only) is (73.4 +7.1 -7.3) SNU. This is 5.3% below the old value of (77.5 + 7.5 -7.8) SNU (PLB 447 (1999) 127-133) with a substantially reduced error. A similar reduction is obtained from the reanalysis of the 51Cr neutrino source experiments of 1994/1995.Comment: Accepted by Physics Letters B January 13, 201

Neutrino Decay as an Explanation of Atmospheric Neutrino Observations

We show that the observed zenith angle dependence of the atmospheric neutrinos can be accounted for by neutrino decay. Furthermore, it is possible to account for all neutrino anomalies with just three flavors.Comment: 4 pages, 1 figur