Phenomenology of the Neutrino-Mass-Giving Higgs Triplet and the Low-Energy Seesaw Violation of Lepton Number

Small realistic Majorana neutrino masses can be generated via a Higgs triplet $(\xi^{++}, \xi^+, \xi^0)$ without having energy scales larger than $M_*={\cal O}(1)$ TeV in the theory. The large effective mass scale $\Lambda$ in the well-known seesaw neutrino-mass operator $\Lambda^{-1} (LL\Phi\Phi)$ is naturally obtained with $\Lambda\sim M_*^2/\mu,$ where $\mu$ is a {\it small} scale of lepton-number violation. In theories with large extra dimensions, the smallness of $\mu$ is naturally obtained by the mechanism of ``shining'' if the number of extra dimensions $n\ge 3.$ We study here the Higgs phenomenology of this model, where the spontaneous violation of lepton number is treated as an external source from extra dimensions. The observable decays $\xi^{++} \to l_i^+l_j^+$ will determine directly the magnitudes of the $\{ij\}$ elements of the neutrino mass matrix. The decays $\xi^+ \to W^+ J^0$ and $\xi^0 \to Z J^0$, where $J^0$ is the massless Goldstone boson (Majoron), are also possible, but of special importance is the decay $\xi^0 \to J^0 J^0$ which provides stringent constraints on the allowed parameter space of this model. Based on the current neutrino data, we also predict observable rates of $\mu-e$ conversion in nuclei.Comment: Minor changes in the text, results unchange

Detailed study of B037 based on {\sl HST} images

B037 is of interest because it is both the most luminous and the most highly reddened cluster known in M31. Images of deep observations and of highly spatial resolutions with the Advanced Camera for Surveys on the {\sl HST} firstly show that this cluster is crossed by a dust lane. Photometric data in the F606W and F814W filters obtained in this paper provide that, colors of ($\rm {F606W-F814W}$) in the dust lane are redder $\sim 0.4$ mags than ones in the other regions of B037. The {\sl HST} images show that, this dust lane seems to be contained in B037, not from the M31 disk or the Milky Way. As we know, the formation of dust requires gas with a rather high metallicity. However, B037 has a low metallicity to be $\rm [Fe/H]=-1.07\pm 0.20$. So, it seems improbable that the observed dust lane is physically associated with B037. It is clear that the origin of this dust lane is worthy of future study. In addition, based on these images, we present the precise variation of ellipticity and position angle, and of surface brightness profile, and determine the structural parameters of B037 by fitting a single-mass isotropic King model. In the F606W filter, we derive the best-fitting scale radius, r_0=0.56\pm0.02\arcsec~(=2.16\pm0.08~\rm{pc}), a tidal radius, r_t=8.6\pm0.4\arcsec~(=33.1\pm1.5~\rm{pc}), and a concentration index $c=\log (r_t/r_0)=1.19\pm0.02$. In the F814W filter, we derive r_0=0.56\pm0.01\arcsec~(=2.16\pm0.04~\rm{pc}), r_t=8.9\pm0.3\arcsec~(=34.3\pm1.2~\rm{pc}), and $c=\log (r_t/r_0)=1.20\pm0.01$. The extinction-corrected central surface brightness is $\mu_0=13.53\pm 0.03~{\rm mag~arcsec^{-2}}$ in the F606W filter, and $12.85\pm 0.03~{\rm mag~arcsec^{-2}}$ in the F814W filter, respectively.Comment: Accepted for Publication in RAA, 13 pages, 5 figures and 7 table

Age and mass studies for young star clusters in M31 from SEDs-fit

In this paper, we present photometry for young star clusters in M31, which are selected from Caldwell et al. These star clusters have been observed as part of the Beijing--Arizona--Taiwan--Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March. The BATC images including these star clusters are taken with 15 intermediate-band filters covering 3000--10000 \AA. Combined with photometry in the {\sl GALEX} far- and near-ultraviolet, broad-band $UBVRI$, SDSS $ugriz$, and infrared $JHK_{\rm s}$ of Two Micron All Sky Survey, we obtain their accurate spectral energy distributions (SEDs) from 1538-20000 \AA. We derive these star clusters' ages and masses by comparing their SEDs with stellar population synthesis models. Our results are in good agreement with previous determinations. The mean value of age and mass of young clusters ($<2$ Gyr) is about 385 Myr and $2\times 10^4 {M_\odot}$, respectively. There are two distinct peaks in the age distribution, a highest peak at age $\sim$ 60 Myr and a secondary peak around 250 Myr, while the mass distribution shows a single peak around $10^4 {M_\odot}$. A few young star clusters have two-body relaxation times greater than their ages, indicating that those clusters have not been well dynamically relaxed and therefore have not established the thermal equilibrium. There are several regions showing aggregations of young star clusters around the 10 kpc ring and the outer ring, indicating that the distribution of the young star clusters is well correlated with M31's star-forming regions. The young massive star clusters (age $\leq 100$ Myr and mass $\geq 10^4 {M_\odot}$) show apparent concentration around the ring splitting region, suggesting a recent passage of a satellite galaxy (M32) through M31 disk.Comment: Accepted for Publication in AJ, 15 pages, 14 figures and 4 table

Age and structure parameters of a remote M31 globular cluster B514 based on HST, 2MASS, GALEX and BATC observations

B514 is a remote M31 globular cluster which locating at a projected distance of R_p~55 kpc. Deep observations with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST) are used to provide the accurate integrated light and star counts of B514. By coupling analysis of the distribution of the integrated light with star counts, we are able to reliably follow the profile of the cluster out to ~40". Based on the combined profile, we study in detail its surface brightness distribution in F606W and F814W filters, and determine its structural parameters by fitting a single-mass isotropic King model. The results showed that, the surface brightness distribution departs from the best-fit King model for r>10". B514 is quite flatted in the inner region, and has a larger half-light radius than majority of normal globular clusters of the same luminosity. It is interesting that, in the M_V versus log R_h plane, B514 lies nearly on the threshold for ordinary globular clusters as defined by Mackey & van den Bergh. In addition, B514 was observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey, using 13 intermediate-band filters covering a wavelength range of 3000--8500 \AA. Based on aperture photometry, we obtain its SEDs as defined by the 13 BATC filters. We determine the cluster's age and mass by comparing its SEDs (from 2267 to 20000{\AA}, comprising photometric data in the near-ultraviolet of GALEX, 5 SDSS bands, 13 BATC intermediate-band, and 2MASS near-infrared JHKs} filters) with theoretical stellar population synthesis models, resulting in age of $11.5\pm3.5$ Gyr. This age confirms the previous suggestion that B514 is an old GC in M31. B514 has a mass of $0.96-1.08 \times 10^6 \rm M_sun$, and is a medium-mass globular cluster in M31.Comment: Accepted for Publication in AJ, 18 pages, 6 figures and 9 table

Neutrino Exotica in the Skew E_6 Left-Right Model

With the particle content of the 27 representation of E_6, a skew left-right supersymmetric gauge model was proposed many years ago, with a variety of interesting phenomenological implications. The neutrino sector of this model offers a natural framework for obtaining small Majorana masses for nu_e, nu_mu, and nu_tau, with the added bonus of accommodating 2 light sterile neutrinos.Comment: 12 pages, no figure, conclusion clarifie

Genome-wide association study in obsessive-compulsive disorder: results from the OCGAS.

Obsessive-compulsive disorder (OCD) is a psychiatric condition characterized by intrusive thoughts and urges and repetitive, intentional behaviors that cause significant distress and impair functioning. The OCD Collaborative Genetics Association Study (OCGAS) is comprised of comprehensively assessed OCD patients with an early age of OCD onset. After application of a stringent quality control protocol, a total of 1065 families (containing 1406 patients with OCD), combined with population-based samples (resulting in a total sample of 5061 individuals), were studied. An integrative analyses pipeline was utilized, involving association testing at single-nucleotide polymorphism (SNP) and gene levels (via a hybrid approach that allowed for combined analyses of the family- and population-based data). The smallest P-value was observed for a marker on chromosome 9 (near PTPRD, P=4.13 × 10(-)(7)). Pre-synaptic PTPRD promotes the differentiation of glutamatergic synapses and interacts with SLITRK3. Together, both proteins selectively regulate the development of inhibitory GABAergic synapses. Although no&nbsp;SNPs were identified as associated with OCD at genome-wide significance level, follow-up analyses of genome-wide association study (GWAS) signals from a previously published OCD study identified significant enrichment (P=0.0176). Secondary analyses of high-confidence interaction partners of DLGAP1 and GRIK2 (both showing evidence for association in our follow-up and the original GWAS study) revealed a trend of association (P=0.075) for a set of genes such as NEUROD6, SV2A, GRIA4, SLC1A2 and PTPRD. Analyses at the gene level revealed association of IQCK and C16orf88 (both P&lt;1 × 10(-)(6), experiment-wide significant), as well as OFCC1 (P=6.29 × 10(-)(5)). The suggestive findings in this study await replication in larger samples