The young cluster NGC 2282 : a multi-wavelength perspective

We present the analysis of the stellar content of NGC~2282, a young cluster in the Monoceros constellation, using deep optical $BVI$ and IPHAS photometry along with infrared (IR) data from UKIDSS and $Spitzer$-IRAC. Based on the stellar surface density analysis using nearest neighborhood method, the radius of the cluster is estimated as $\sim$ 3.15\arcmin. From optical spectroscopic analysis of 8 bright sources, we have classified three early B-type members in the cluster, which includes, HD 289120, a previously known B2V type star, a Herbig Ae/Be star (B0.5 Ve) and a B5 V star. From spectrophotometric analyses, the distance to the cluster has been estimated as $\sim$ 1.65 kpc. The $K$-band extinction map is estimated using nearest neighborhood technique, and the mean extinction within the cluster area is found to be A$_V$ $\sim$ 3.9 mag. Using IR colour-colour criteria and H$_\alpha$-emission properties, we have identified a total of 152 candidate young stellar objects (YSOs) in the region, of which, 75 are classified as Class II, 9 are Class I YSOs. Our YSO catalog also includes 50 H$_\alpha$-emission line sources, identified using slitless spectroscopy and IPHAS photometry data. Based on the optical and near-IR colour-magnitude diagram analyses, the cluster age has been estimated to be in the range of 2 $-$ 5 Myr, which is in agreement with the estimated age from disc fraction ($\sim$ 58\%). Masses of these YSOs are found to be $\sim$ 0.1$-$2.0 M$_\odot$. Spatial distribution of the candidate YSOs shows spherical morphology, more or less similar to the surface density map.Comment: 16 pages, 19 Figure

Evidence of mobile carriers with Charge Ordering gap in Epitaxial Pr0.625_{0.625}Ca0.375_{0.375}MnO3_{3} Thin Films

Epitaxial thin films of charge-ordered Pr$_{0.625}$Ca$_{0.375}$MnO$_{3}$ have been studied using variable temperature Scanning tunneling microscopy and spectroscopy (STM/STS). The as grown films were found to be granular while the annealed films show atomic terraces at all temperatures and are found to be electronically homogeneous in 78-300K temperature range. At high temperatures (T$>$T$_{CO}\approx$ 230 K) the local tunnel spectra of the annealed films show a depression in the density of states (DOS) near Fermi energy implying a pseudogap with a significant DOS at E$_F$. The gap feature becomes more robust with cooling with a sharp jump in DOS at E$_F$ at T$_{CO}$ and with a gap value of $\sim$0.3 eV at 78K. At low temperatures we find a small but finite DOS at E$_F$ indicative of some delocalized carriers in the CO phase together with an energy gap. This is consistent with bulk transport, which shows weakening of the activation gap with cooling below 200K, and indicates the presence of two types of carriers at low temperatures.Comment: 4 pages, 4 figure

Incidence of HI 21-cm absorption in strong FeII systems at 0.5<z<1.50.5<z<1.5

We present the results from our search for HI 21-cm absorption in a sample of 16 strong FeII systems ($W_{\rm r}$(MgII $\lambda2796$) $\ge1.0$ \AA\ and $W_{\rm r}$(FeII $\lambda2600$) or $W_{\rm FeII}$ $\ge1$ \AA) at $0.5<z<1.5$ using the Giant Metrewave Radio Telescope and the Green Bank Telescope. We report six new HI 21-cm absorption detections from our sample, which have increased the known number of detections in strong MgII systems at this redshift range by $\sim50$%. Combining our measurements with those in the literature, we find that the detection rate of HI 21-cm absorption increases with $W_{\rm FeII}$, being four times higher in systems with $W_{\rm FeII}$ $\ge1$ \AA\ compared to systems with $W_{\rm FeII}$ $<1$ \AA. The $N$(HI) associated with the HI 21-cm absorbers would be $\ge 2 \times 10^{20}$ cm$^{-2}$, assuming a spin temperature of $\sim500$ K (based on HI 21-cm absorption measurements of damped Lyman-$\alpha$ systems at this redshift range) and unit covering factor. We find that HI 21-cm absorption arises on an average in systems with stronger metal absorption. We also find that quasars with HI 21-cm absorption detected towards them have systematically higher $E(B-V)$ values than those which do not. Further, by comparing the velocity widths of HI 21-cm absorption lines detected in absorption- and galaxy-selected samples, we find that they show an increasing trend (significant at $3.8\sigma$) with redshift at $z<3.5$, which could imply that the absorption originates from more massive galaxy haloes at high-$z$. Increasing the number of HI 21-cm absorption detections at these redshifts is important to confirm various trends noted here with higher statistical significance.Comment: 17 pages, 10 figures, 8 tables, accepted for publication in MNRA

Why small business owners should not worry about "money left on the table" in IPOs!

Purpose – this study aims to investigate how those directors of listed companies to make profits when their firms were listed to public. Design/methodology/approach –This is an empirical study; we adopted the formula from Ritter (2001) for this research. Findings -this study finds that directors of issuing companies usually get benefits from the money left on the table due to two factors. First, they usually retain larger percentage of shares before or after the companies going public; second, the first-day closing market price is normally higher than the initial file price ranges (defined as the expected price per share by issuing companies just before the firms go public). Originality/value - the findings may be used for future academic research literatures which focus on IPO or primary market. This research would help individual investors better understanding primary market especially IPO market