Optimal operating conditions and characteristics of acetone/CaF_2 detector for inverse photoemission spectroscopy

Performance and characteristics of a band-pass photon detector using acetone gas and CaF_2 window (acetone/CaF_2) have been studied and compared with an ethanol/MgF_2 detector. The optimal operating conditions are found to be 4 mbar acetone pressure and 745+/-20 V anode voltage. The count rate obtained by us is about a factor of 3 higher than what has been reported earlier for the acetone detector. Unlike other gas filled detectors, this detector works in the proportional region with very small dead time (4 micro sec). A detector band-pass of 0.48+/-0.01 eV FWHM is obtained.Comment: Review of Scientific Instruments 76, 066102 (2005

Low-Mass Dileptons at the CERN-SpS: Evidence for Chiral Restoration?

Using a rather complete description of the in-medium $\rho$ spectral function - being constrained by various independent experimental information - we calculate pertinent dilepton production rates from hot and dense hadronic matter. The strong broadening of the $\rho$ resonance entails a reminiscence to perturbative $q\bar q$ annihilation rates in the vicinity of the phase boundary. The application to dilepton observables in Pb(158AGeV)+Au collisions - incorporating recent information on the hadro-chemical composition at CERN-SpS energies - essentially supports the broadening scenario. Possible implications for the nature of chiral symmetry restoration are outlined.Comment: 6 pages ReVTeX including 5 eps-figure

Influence of Ni doping on the electronic structure of Ni_2MnGa

The modifications in the electronic structure of Ni_{2+x}Mn_{1-x}Ga by Ni doping have been studied using full potential linearized augmented plane wave method and ultra-violet photoemission spectroscopy. Ni 3d related electron states appear due to formation of Ni clusters. We show the possibility of changing the minority-spin DOS with Ni doping, while the majority-spin DOS remains almost unchanged. The total magnetic moment decreases with excess Ni. The total energy calculations corroborate the experimentally reported changes in the Curie temperature and the martensitic transition temperature with x.Comment: 4 pages, 4 figures, accepted in Phys. Rev.

Fabrication of an inverse photoemission spectrometer to study unoccupied electronic states

We discuss the performance of an inverse photoemission spectrometer that has been recently fabricated in our laboratory. The photon detector is of band-pass type with acetone gas filling and CaF2 window (acetone/ CaF2). We determine the optimal operating conditions of the detector to be 4 mbar acetone pressure and 745 ± 20 V anode voltage. At these operating conditions, the count rate is improved by a factor of three to what has been reported earlier by Funnemann and Merz. We show that unlike other gas-filled detectors, acetone/CaF2 detector works in the proportional region. Its dead time is negligible and addition of multiplier gas like argon worsens its performance. The performance of this detector has been compared with an ethanol/MgF2 detector. High count rate, reasonable resolution, negligible dead time, no requirement of multiplier or quench gas, satisfactory stability, and ease of handling make the acetone/CaF2 detector an attractive candidate for use in inverse photoemission spectroscopy (IPES). A low-energy electron gun of Stoffel-Johnson type has been fabricated and the beam current profile has been determined as a function of electron kinetic energy. The IPES spectra of polycrystalline Ag and Ta are shown and compared with data in the literature. By fitting the IPES Fermi edge of Ag, we find the overall resolution of the spectrometer to be 0.55 eV and the band-pass of acetone/CaF2 detector to be 0.48 eV FWHM

Magnetoresistance behavior of a ferromagnetic shape memory alloy: Ni_1.75Mn_1.25Ga

A negative-positive-negative switching behavior of magnetoresistance (MR) with temperature is observed in a ferromagnetic shape memory alloy Ni_1.75Mn_1.25Ga. In the austenitic phase between 300 and 120 K, MR is negative due to s-d scattering. Curiously, below 120K MR is positive, while at still lower temperatures in the martensitic phase, MR is negative again. The positive MR cannot be explained by Lorentz contribution and is related to a magnetic transition. Evidence for this is obtained from ab initio density functional theory, a decrease in magnetization and resistivity upturn at 120 K. Theory shows that a ferrimagnetic state with anti-ferromagnetic alignment between the local magnetic moments of the Mn atoms is the energetically favoured ground state. In the martensitic phase, there are two competing factors that govern the MR behavior: a dominant negative trend up to the saturation field due to the decrease of electron scattering at twin and domain boundaries; and a weaker positive trend due to the ferrimagnetic nature of the magnetic state. MR exhibits a hysteresis between heating and cooling that is related to the first order nature of the martensitic phase transition.Comment: 17 pages, 5 figures. Accepted in Phys. Rev.

Effect of Integrated Nutrient Management on Vegetative Growth and Yield in Mango Cv. Himsagar

An experiment was conducted to study the effect of various combinations of integrated nutrient management schedules on vegetative growth and yield in mango cv. Himsagar at Regional Research Station, Gayeshpur, B.C.K.V., Nadia, West Bengal, during the years 2009-2011. Maximum total increment in plant height (108.00 cm), plant spread in E-W direction (123.00 cm) and N-S direction (105.00 cm), and tree volume (85.95 m3) was recorded in 500:250:250g NPK/tree/year + 50kg FYM + 250g Azospirillium (T6) compared to that in other treatments. This treatment (T6) also significantly increased total number of fruits (234.12 fruits / tree), average fruit weight (263.10g) and yield (58.56kg /tree)

Analysis of characteristics of semantics of spoken language in normally developing Hindi speaking children

Background: There appears to be a lack of database of and dearth of studies focusing on the characteristics of semantics in Hindi speaking school aged children. Such a data base will be useful for building vocabulary for language disordered children and for constructing AAC boards for non-verbal children. Hence, it is essential to study the characteristics of semantics of normally developing children. This paper focuses on describing the semantic characteristics of spoken language in Hindi speaking children.Methods: 200 normally developing Hindi speaking children within the age group of 3 - 7 years were shown and instructed to describe three validated pictures of daily events. The responses were recorded and transcribed.  Analyses included type-token ratio, frequency of occurrence and comparisons between different word classes.Results: Percentage of nouns is highest followed by verbs, pronouns, adjectives. Frequency of occurrence of words increases with increase in age. The common words with high frequency of occurrence are hƐ, hũ, rΛhe, rΛha, rΛhi, dƷa, ɔr, khel, gaɖi, log, pe, ke.  There appears to be marked increase in different classes of words, one at 4 yrs of age (after Sr. KG) and other at 6 yrs of age (standard I).Conclusions: One of the highlighting features of this study is the huge database of semantics (of spoken language) collected from 200 school going children.  Creating such a database and utilizing it for assessing language of the disordered population appears to be the need of the hour.

Pendekatan Pastoral Konseling Sebagai Sarana Peningkatan Kesehatan Mental Di SMTK Sabu Raijua

SMTK Sabu Raijua adalah salah satu satuan pendidikan dengan jenjang SMTK yang berlokasi di Dusun  Ledemanu, Desa Raenyale, Kecamatan Sabu Barat, Kabupaten Sabu Raijua, Nusa Tenggara Timur. Kebijakan yang diterapkan oleh Pemerintah di masa Pandemi Covid-19 yang ada memunculkan persoalan-persoalan yang muncul di bidang pendidikan, salah satunya di SMTK Sabu Raijua. Jumlah tenaga kependidikan yang terbatas membuat para guru di sekolah ini harus mengerjakan dua tugas sekaligus sehingga menyebabkan beban kerja semakin bertambah dan menumpuk yang tidak jarang menyebabkan stres. Bagi para siswa, kebijakan untuk belajar dari rumah juga menimbulkan stres akibat keterbatasan dan kualitas jaringan internet yang buruk sehingga tidak memungkinkan dilaksanakannya pembelajaran secara online dan berakibatnya pada kesulitan untuk menerima dan memahami materi yang ada. Menyikapi situasi ini, IAKN Kupang melaui program studi Pastoral Konseling menyelenggarakan Kegiatan pengabdian kepada masyarakat (PKM). PKM  ini bertujuan dalam rangka meningkatkan kesehatan mental di SMTK Sabu Raijua dengan metode Participatory Action Research (PAR) dalam bentuk seminar, Focus Group Discussions (FGD), dan pelatihan terapi relaksasi otot progresif (proggresive muscle relaxation). Dari hasil evaluasi  menunjukkan bahwa para peserta memiliki pemahaman yang baik tentang kesehatan mental dan kegiatan PKM ini sesuai dengan harapan merek

Generalization of escape rate from a metastable state driven by external cross-correlated noise processes

We propose generalization of escape rate from a metastable state for externally driven correlated noise processes in one dimension. In addition to the internal non-Markovian thermal fluctuations, the external correlated noise processes we consider are Gaussian, stationary in nature and are of Ornstein-Uhlenbeck type. Based on a Fokker-Planck description of the effective noise processes with finite memory we derive the generalized escape rate from a metastable state in the moderate to large damping limit and investigate the effect of degree of correlation on the resulting rate. Comparison of the theoretical expression with numerical simulation gives a satisfactory agreement and shows that by increasing the degree of external noise correlation one can enhance the escape rate through the dressed effective noise strength.Comment: 9 pages, 1 figur