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We report measurements of H I content in 11 nearby, actively star-forming, blue compact dwarf galaxies (BCDs) from 21 cm observations with the Arecibo telescope. These BCDs, selected by their red (W2[4.6 $\mu$m]$-$W3[12 $\mu$m]$>$3.8 mag) and bright mid-infrared (MIR) emission (W4[22 $\mu$m]$<$ 7.6 mag), have high specific star formation rates (median sSFR $\sim$10$^{-7.8}$ yr$^{-1}$), similar to high redshift galaxies. H I emission was detected in six sources. We analyze our new detections in the context of previous H I observations of 218 dwarf irregulars (dIs) and BCDs in the literature. The $M_{\rm HI}$-$M_{\ast}$ relation resulting from our observations confirms the dominating fraction of H I gas among baryons in galaxies with lower stellar masses. This Arecibo BCD sample has significantly lower median H I depletion timescales ($\tau_{\rm HI}\sim$ 0.3 Gyr) than other dIs/BCDs ($\sim$ 6.3 Gyr) in the literature. The majority of the sources (10/11) in the Arecibo sample are very red in W1[3.4 $\mu$m]$-$W2[4.6 $\mu$m] colour ($>$ 0.8 mag) implying the presence of warm dust. We investigate the relation of $\tau_{\rm HI}$ with stellar mass ($M_{\ast}$) and sSFR. We find that $\tau_{\rm HI}$ is significantly anti-correlated with $M_{\ast}$ for higher sSFR ($>$10$^{-8.5}$ yr$^{-1}$) and with sSFR for higher stellar mass ($>10^{7.5}\,{\rm M}_{\odot}$) dwarf galaxies. The high sSFR for the BCDs in the Arecibo observed sample is mainly due to their high atomic gas star formation efficiency (SFE) or low $\tau_{\rm HI}$. The low $\tau_{\rm HI}$ or high SFE in these sources is possibly due to runaway star formation in compact and dense super star clusters., Comment: 17(12+5) pages, 7(6+1)figures, 6(4+2) tables, accepted for publication in MNRAS

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) has started the Commensal Radio Astronomy FasT Survey (CRAFTS). In this paper, we use the technical parameters of FAST derived from commissioning observations to simulate the completeness function for extragalactic HI survey of CRAFTS, HI galaxies from two kinds of mock catalogues are selected. One is generated by Monte-Carlo simulation based on the interpolated mass-velocity width function of the ALFALFA $100\%$ (a.k.a. $\alpha$ .100) catalogue. The other is constructed by semi-analytical N-body simulation based on the $\Lambda$CDM model. Our results suggest that a two-pass extragalactic HI survey will be able to detect nearly $4.8\times10^{5}$ galaxies, from which the 'faint end' slope of the HI Mass Function (HIMF) can be recovered to $\mathrm{10^{7}\, M_{\odot}}$ and the 'knee mass' of the HIMF can be measured to a redshift of 0.1. Considering the radio frequency interference status and sensitivity limitation, CRAFTS will be efficient in detecting HI galaxies at redshifts below 0.1, which implies a tremendous potential in exploring the galaxy interactions in different environments and the spatial distribution of HI galaxies in the local universe., Comment: 15 pages, 12 figures

The Arecibo L-band Feed Array Zone of Avoidance (ALFAZOA) Shallow Survey is a blind HI survey of the extragalactic sky behind the northern Milky Way conducted with the ALFA receiver on the 305m Arecibo Radio Telescope. ALFAZOA Shallow covered 900 square degrees at full sensitivity from 30{\deg} ${\leq} l {\leq} $75{\deg} and |b|$ {\leq}$ 10{\deg} and an additional 460 square degrees at limited sensitivity at latitudes up to 20{\deg}. It has an rms sensitivity of 5-7 mJy and a velocity resolution of 9 - 20.6 km s$^{-1}$, and detected 403 galaxies out to a recessional velocity of 12,000 km s$^{-1}$, with an angular resolution of 3.4' and a positional accuracy between 0.2' and 1.7'. The survey is complete above an integrated line flux $F_{HI}$ = 2.0 Jy km s$^{-1}$ for half the survey, and above $F_{HI}$ = 2.8 Jy km s$^{-1}$ for the other half. Forty-three percent of the ALFAZOA HI detections have at least one possible optical/NIR counterpart in the literature, and an additional 16% have counterparts that only included previous HI measurements. There are fewer counterparts in regions of high extinction and for galaxies with lower HI mass. Comparing the results of the survey to the predictions of Erdogdu et al. (2006), and using their nomenclature, ALFAZOA confirms the position and extent in the ZOA of the C7, C${\zeta}$, Pegasus, Corona Borealis and Delphinus structures, but not of the Cygnus void. Two new structures are identified, both connected to the C7 overdensity; one extends to 35{\deg}, and the other crosses the ZOA., Comment: 19 pages, 18 figures, accepted for publication in the Astronomical Journal

The Survey of Ionized Gas of the Galaxy, Made with the Arecibo telescope (SIGGMA) provides a fully-sampled view of the radio recombination line (RRL) emission from the portion of the Galactic plane visible by Arecibo. Observations use the Arecibo L-band Feed Array (ALFA), which has a FWHM beam size of 3.4 arcmin. Twelve hydrogen RRLs from H163$\alpha$ to H174$\alpha$ are located within the instantaneous bandpass from 1225 MHz to 1525 MHz. We provide here cubes of average ("stacked") RRL emission for the inner Galaxy region $32 \le \ell \le 70$ degrees, $|b|\le1.5$ degree, with an angular resolution of 6 arcmin. The stacked RRL rms at 5.1 km/s velocity resolution is $\sim0.65$ mJy beam$^{-1}$, making this the most sensitive large-scale fully-sampled RRL survey extant. We use SIGGMA data to catalogue 319 RRL detections in the direction of 244 known HII regions, and 108 new detections in the direction of 79 HII region candidates. We identify 11 Carbon RRL emission regions, all of which are spatially coincident with known HII regions. We detect RRL emission in the direction of 14 of the 32 supernova remnants (SNRs) found in the survey area. This RRL emission frequently has the same morphology as the SNRs. The RRL velocities give kinematic distances in agreement with those found in the literature, indicating that RRLs may provide an additional tool to constrain distances to SNRs. Finally, we analyze the two bright star-forming complexes: W49 and W51. We discuss the possible origins of the RRL emission in directions of SNRs W49B and W51C.

The Arecibo L-Band Feed Array Zone of Avoidance (ALFA ZOA) Deep Survey is the deepest and most sensitive blind Hi survey undertaken in the ZOA. ALFA ZOA Deep will cover about 300 square degrees of sky behind the Galactic plane in both the inner (30 deg < l < 75 deg; b < |2 deg|) and outer (175 deg < l < 207 deg; -2 deg < b < +1 deg) Galaxy, using the Arecibo Radio Telescope. First results from the survey have found 61 galaxies within a 15 square degree area centered on l = 192 deg and b = -2 deg. The survey reached its expected sensitivity of rms = 1 mJy at 9 km/s channel resolution, and is shown to be complete above integrated flux, F_HI = 0.5 Jy km/s. The positional accuracy of the survey is 28 arcsec and detections are found out to a recessional velocity of nearly 19,000 km/s. The survey confirms the extent of the Orion and Abell 539 clusters behind the plane of the Milky Way and discovers expansive voids, at 10,000 km/s and 18,000 km/s. 26 detections (43%) have a counterpart in the literature, but only two of these have known redshift. Counterparts are 20% less common beyond v_hel = 10,000 km/s and 33% less common at extinctions higher than AB = 3.5 mag. ALFA ZOA Deep survey is able to probe large scale structure beyond redshifts that even the most modern wide-angle surveys have been able to detect in the Zone of Avoidance at any wavelength., Comment: 49 pages, Accepted by AJ, AASTeX5.2

The Arecibo L-Band Feed Array Zone of Avoidance (ALFA ZOA) Survey has discovered a nearby galaxy, ALFA ZOA J1952+1428, at a heliocentric velocity of +279 km s-1. The galaxy was discovered at low Galactic latitude by 21-cm emission from neutral hydrogen (Hi). We have obtained follow-up observations with the EVLA and the 0.9-m SARA optical telescope. The Hi distribution overlaps an uncataloged, potential optical counterpart. The Hi linear size is 1.4 kpc at our adopted distance of D = 7 Mpc, but the distance estimate is uncertain as Hubble's law is unreliable at low recessional velocities. The optical counterpart has mB = 16.9 mag and B - R = 0.1 mag. These characteristics, including MHI = 107.0 M\odot and LB = 107.5 L\odot, if at 7 Mpc, indicate that this galaxy is a blue compact dwarf, but this remains uncertain until further follow-up observations are complete. Optical follow-up observations are ongoing and near infrared follow-up observations have been scheduled., Comment: 4 pages, 3 figures, compiled with emulateapj, accepted by ApJL in special edition on early science with the EVLA

We report the discovery of a new detached eclipsing binary known as NSVS01031772 with component masses M_1= 0.5428 +/- 0.0027Msun, M_2= 0.4982 +/- 0.0025Msun, and radii R_1= 0.5260 +/- 0.0028Rsun, R_2= 0.5088 +/- 0.0030Rsun. The system has an orbital period of 0.3681414(3) days and an apparent magnitude V ~ 12.6. The estimated effective temperatures of the stars are T_eff1 = 3615 +/- 72K and T_eff2 = 3513 +/- 31K. The space velocities of the system suggest that it is a main sequence binary and with a metallicity that is approximately solar. The two stars in this binary are located in a region of the Mass-Radius relation where no accurate observational data were previously available. Similarly to other low-mass binaries recently studied, the radius of each star in NSVS01031772 exceeds the best evolutionary model predictions by about 8.5% on average., Comment: 11 pages, 6 figures (low resolution), 5 tables. Submitted to ApJ