A survey of nearby galaxies for CO

We have made a survey of the nuclei of 81 galaxies for the 1-) line of CO. 38 of the galaxies are from a complete sample with recession velocity ≦400 km s-1 and 21-cm line strength ≧10-27 Wm-2, and the remainder represent nearby galaxies with weaker or no HI, early-type galaxies (E/SO/Sa) with detected HI and active/infrared galaxies. Galaxies with strong CO lines like M82, NGC253 and IC342 are exceedingly rare: all the galaxies we observed are weaker than 0/2K except the irregular galaxy DDO133 with T*A=0.22K. We have new, confirmed detections of two other irregular galaxies, IC10 and Pegasus, at a weaker level, and unconfirmed detections of the irregular NGC3109 and the nearest Type I Seyfert galaxy NGC4051. We have confirmed the existence of CO in the nucleus of NGC6946 and obtained spectra of new positions in M82 and NGC253

Large-scale structure in a new deep IRAS galaxy redshift survey

We present here the first results from two recently completed, fully sampled redshift surveys comprising 3703 IRAS Faint Source Survey (FSS) galaxies. An unbiased counts-in-cells analysis finds a clustering strength in broad agreement with other recent redshift surveys and at odds with the standard cold dark matter model. We combine our data with those from the QDOT and 1.2 Jy surveys, producing a single estimate of the IRAS galaxy clustering strength. We compare the data with the power spectrum derived from a mixed dark matter universe. Direct comparison of the clustering strength seen in the IRAS samples with that seen in the APM-Stromlo survey suggests b_O/b_I=1.20+/-0.05 assuming a linear, scale independent biasing. We also perform a cell by cell comparison of our FSS-z sample with galaxies from the first CfA slice, testing the viability of a linear-biasing scheme linking the two. We are able to rule out models in which the FSS-z galaxies identically trace the CfA galaxies on scales 5-20h^{-1}Mpc. On scales of 5 and 10h^{-1}Mpc no linear-biasing model can be found relating the two samples. We argue that this result is expected since the CfA sample includes more elliptical galaxies which have different clustering properties from spirals. On scales of 20h^{-1}Mpc no linear-biasing model with b_O/b_I < 1.70 is acceptable. When comparing the FSS-z galaxies to the CfA spirals, however, the two populations trace the same structures within our uncertaintie

IRAS observations of NGC 1052

The galaxy NGC 1052 has been observed with the IRAS satellite. The infrared emission at 100 microns is substantially larger than a smooth extrapolation of the radio data. Because of the large diaphragm size of IRAS, it is impossible to decide uniquely if the infrared radiation represents a self-absorbed nonthermal spectrum or thermal reradiation by heated dust

Detection of HTLV-1 proviral DNA in cell-free DNA: potential for non-invasive monitoring of Adult T cell leukaemia/lymphoma using liquid biopsy?

Introduction: Fragmented genomic DNA is constitutively released from dying cells into interstitial fluid in healthy tissue. In cancer, this so-called ‘cell-free’ DNA (cfDNA) released from dying malignant cells encodes cancer-associated mutations. Thus, minimally invasive sampling of cfDNA in blood plasma can be used to diagnose, characterise and longitudinally monitor solid tumours at remote sites in the body. ~5% of carriers of Human T cell leukaemia virus type 1 (HTLV-1) develop Adult T cell leukaemia/lymphoma (ATL), and a similar percentage develop an inflammatory CNS disease, HTLV-1 associated myelopathy (HAM). In both ATL and HAM, high frequencies of HTLV-1 infected cells are present in the affected tissue: each carrying an integrated DNA copy of the provirus. We hypothesised that turnover of infected cells results in the release of HTLV-1 proviruses in cfDNA, and that analysis of cfDNA from infected cells in HTLV-1 carriers might contain clinically useful information pertaining to inaccessible sites in the body- e.g. for early detection of primary or relapsing localised lymphoma type ATL. To evaluate the feasibility of this approach, we tested for HTLV-1 proviruses in blood plasma cfDNA. Methods: CfDNA (from blood plasma) and genomic DNA (gDNA, from peripheral blood mononuclear cells, PBMC) was isolated from blood from 6 uninfected controls, 24 asymptomatic carriers (AC), 21 patients with HAM and 25 patients with ATL. Proviral (HTLV-1 Tax) and human genomic DNA (the beta globin gene, HBB) targets were quantified by qPCR using primer pairs optimised for fragmented DNA. Results: Pure, high quality cfDNA was successfully extracted from blood plasma of all study participants. When compared with uninfected controls, HTLV-1 carriers had higher concentrations of cfDNA circulating in their blood plasma. Patients with ATL who were not in remission had the highest levels of blood plasma cfDNA in any group studied. HTLV-1 proviral DNA was detected in 60/70 samples obtained from HTLV-1 carriers. The proviral load (percentage of cells carrying proviruses) was approximately tenfold lower in plasma cfDNA than in PBMC genomic DNA, and there was a strong correlation between the proviral load in cfDNA and PBMC genomic DNA in HTLV-1 carriers that did not have ATL. cfDNA samples in which proviruses were undetectable also had very low proviral load in PBMC genomic DNA. Finally, detection of proviruses in cfDNA of patients with ATL was predictive of clinical status: patients with evolving disease had higher than expected total amount of proviruses detectable in plasma cfDNA. Discussion: We demonstrated that (1) HTLV-1 infection is associated with increased levels of blood plasma cfDNA, (2) proviral DNA is released into blood plasma cfDNA in HTLV-1 carriers and (3) proviral burden in cfDNA correlates with clinical status, raising the possibility of developing assays of cfDNA for clinical use in HTLV-1 carriers

Optical/Near-Infrared Imaging of Infrared-Excess Palomar-Green QSOs

Ground-based high spatial-resolution (FWHM < 0.3-0.8") optical and near-infrared imaging (0.4-2.2um) is presented for a complete sample of optically selected Palomar-Green QSOs with far-infrared excesses at least as great as those of "warm" AGN-like ultraluminous infrared galaxies (L_ir/L_big-blue-bump > 0.46). In all cases, the host galaxies of the QSOs were detected and most have discernable two-dimensional structure. The QSO host galaxies and the QSO nuclei are similar in magnitude at H-band. H-band luminosities of the hosts range from 0.5-7.5 L* with a mean of 2.3 L*, and are consistent with those found in ULIGs. Both the QSO nuclei and the host galaxies have near-infrared excesses, which may be the result of dust associated with the nucleus and of recent dusty star formation in the host. These results suggest that some, but not all, optically-selected QSOs may have evolved from an infrared-active state triggered by the merger of two similarly-sized L* galaxies, in a manner similar to that of the ultraluminous infrared galaxies.Comment: Aastex format, 38 pages, 4 tables, 10 figures. Higher quality figures are available in JPG forma

Astromineralogy of the 13 μm Feature in the Spectra of Oxygen-rich Asymptotic Giant Branch Stars. I. Corundum and Spinel

http://iopscience.iop.org/0004-637X/640/2/971/pdf/0004-637X_640_2_971.pdfAsymptotic giant branch (AGB) stars have several interesting infrared spectral features. Approximately half the oxygen-rich AGB stars to be investigated spectroscopically exhibit a feature at ~13 μm. The carrier of this feature has not yet been unequivocally identified but has been attributed to various dust species, including corundum (α-Al2O 3), spinel (MgAl2O4), and silica (SiO 2). In order to constrain the carrier of the 13 μm feature, we have used the one-dimensional radiative transfer code DUSTY to model the effects of composition and optical depth on the shape and strength of the emerging 13 μm feature from corundum and spinel grains. We have modeled various corundum, spinel, corundum-silicate, and spinel-silicate mixtures in dust shells surrounding O-rich AGB stars. These models demonstrate that (1) if corundum is present in these circumstellar dust shells, even at very low relative abundances, a ~13 μm feature should be observed; (2) corundum's weak ~21 μm feature will not be observed, even if it is responsible for the ~13 μm feature; (3) even at low relative abundances, spinel exhibits a feature at 16.8 μm that is not found in observations; and (4) the grains must be spherical. Other grain shapes (spheroids, ellipsoids, and hollow spheres) shift the features to longer wavelengths for both spinel and corundum. Our models show that spinel is unlikely to be the carrier of the 13 μm feature. The case for corundum as the carrier is strengthened but not yet proven.This work is supported in part by NASA grant APRA04-0000-0041

HST Imaging Polarimetry of the Gravitational Lens FSC10214+4724

We present imaging polarimetry of the extremely luminous, redshift 2.3 IRAS source FSC10214+4724. The observations were obtained with HST's Faint Object Camera in the F437M filter, which is free of strong emission lines. The 0.7 arcsec long arc is unresolved to 0.04 arcsec FWHM in the transverse direction, and has an integrated polarization of 28 +/- 3 percent, in good agreement with ground-based observations. The polarization position angle varies along the arc by up to 35 deg. The overall position angle is 62 +/- 3 deg east of north. No counterimage is detected to B = 27.5 mag ($3\sigma$), giving an observed arc to counterimage flux ratio greater than 250, considerably greater than the flux ratio of 100 measured previously in the I-band. This implies that the configuration of the object in the source plane at the B-band is different from that at I-band, and/or that the lensing galaxy is dusty.Comment: 17 pages, 3 figures. Accepted for publication in Astronomical Journal, February 199

The Extinction Towards the GRB970228 Field

We determine the local galactic extinction towards the field of gamma-ray burst GRB970228 using a variety of methods. We develop a maximum likelihood method for measuring the extinction by comparing galaxy counts in the field of interest to those in a field of known extinction, and apply this method to the GRB970228 field. We also measure the extinction by comparing the observed stellar spectral energy distributions of stars in the GRB970228 field to the spectral energy distribution of library spectra of the same spectral type. Finally we estimate the extinction using the Balmer emission line ratios of a galaxy in the GRB970228 field, and the neutral hydrogen column density and amount of infrared dust emission toward this field. Combining the results of these methods, we find a best-fit galactic extinction in the optical of $A_V=1.19^{+0.10}_{-0.17}$, which implies a a substantial dimming and change of the spectral slope of the intrinsic GRB970228 afterglow.Comment: 22 pages, including 7 figures. Submitted to Ap

A 25 micron component in 3C 390.3

Infrared Astronomical Satellite (IRAS) observations show that there is a maximum in the continuum energy distribution of the broad-line radio galaxy 3C 390.3 near 25µm and that this active galaxy emits most of its energy in the infrared. If the 25µm component is thermal, its temperature is approximately 180 K, and its size must exceed tens of parsecs

Motion and gravitational wave forms of eccentric compact binaries with orbital-angular-momentum-aligned spins under next-to-leading order in spin-orbit and leading order in spin(1)-spin(2) and spin-squared couplings

A quasi-Keplerian parameterisation for the solutions of second post-Newtonian (PN) accurate equations of motion for spinning compact binaries is obtained including leading order spin-spin and next-to-leading order spin-orbit interactions. Rotational deformation of the compact objects is incorporated. For arbitrary mass ratios the spin orientations are taken to be parallel or anti-parallel to the orbital angular momentum vector. The emitted gravitational wave forms are given in analytic form up to 2PN point particle, 1.5PN spin orbit and 1PN spin-spin contributions, where the spins are counted of 0PN order.Comment: 26 pages, 1 figure, published in CQG. Current version: we removed a remark and clarified the derivation of the orbital element \e_ph