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We measure the two-point clustering of spectroscopically confirmed quasars from the final sample of the Baryon Oscillation Spectroscopic Survey (BOSS) on comoving scales of 4 ≤ s ≤ 22h-1Mpc. The sample covers 6950deg² [ ~ 19(h-1Gpc)³] and, over the redshift range 2.2 ≤ z ≤ 2.8, contains 55 826 homogeneously selected quasars, which is twice as many as in any similar work. We deduce bQ = 3.54 ± 0.10; the most precise measurement of quasar bias to date at these redshifts. This corresponds to a host halo mass of ~2 × 1012h-1M⊙ with an implied quasar duty cycle of ~1 per cent. The real-space projected correlation function is well fitted by a power law of index 2 and correlation length r0 = (8.12 ± 0.22)h-1 Mpc over scales of 4 ≲ rp ≲ 25h-1 Mpc. To better study the evolution of quasar clustering at moderate redshift, we extend the redshift range of our study to z ~ 3.4 and measure the bias and correlation length of three subsamples over 2.2 ≤ z ≤ 3.4. We find no significant evolution of r0 or bias over this range, implying that the host halo mass of quasars decreases somewhat with increasing redshift. We find quasar clustering remains similar over a decade in luminosity, contradicting a scenario in which quasar luminosity is monotonically related to halo mass at z ≈ 2.5. Our results are broadly consistent with previous BOSS measurements, but they yield more precise constraints based upon a larger and more uniform data set. [ABSTRACT FROM AUTHOR]

We present the distances of 9792 spiral galaxies lying within 15,000 km s−1 using the relation between luminosity and rotation rate of spiral galaxies. The sample is dominantly, but not exclusively, drawn from galaxies detected in the course of the ALFALFA H i survey with the Arecibo Telescope. Relations between H i line widths and luminosity are calibrated at SDSS u, g, r, i, z bands and WISE W1 and W2 bands. By exploiting secondary parameters, particularly color indices, we address discrepancies between measured distances at different wave bands with unprecedented detail. We provide a catalog that includes reduced kinematic, photometric, and inclination parameters. We also describe a machine-learning algorithm, based on the random forest technique, that predicts the dust attenuation in spirals lacking infrared photometry. We determine a Hubble Constant value of H0 = 75.1 ± 0.2(stat.), with potential systematics up to ±3 km s−1 Mpc−1. [ABSTRACT FROM AUTHOR]

We examine recent high-precision measurements of small-scale quasar clustering (at z ∼ 0.5–2 on scales of |${\sim }25~\mathrm{kpc}\, h^{-1}$|⁠) from the SDSS in the context of the MassiveBlack II (MBII) cosmological hydrodynamic simulation and conditional luminosity function (CLF) modelling. At these high luminosities (g < 20.85 quasars), the MBII simulation volume (⁠|$100~\mathrm{cMpc}\, h^{-1}$| comoving boxsize) has only three quasar pairs at distances of 1–4 Mpc. The black hole masses for the pairs range between |$M_{\rm bh}\sim 1{\, \rm and\, }3\times 10^{9}~\mathrm{M}_{\odot }\, h^{-1}$| and the quasar hosts are haloes of |$M_{\rm h}\sim 1\hbox{--}3\times 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$|⁠. Such pairs show signs of recent major mergers in the MBII simulation. By modelling the central and satellite AGN CLFs as lognormal and Schechter distributions, respectively (as seen in MBII AGNs), we arrive at CLF models which fit the simulation predictions and observed luminosity function and the small-scale clustering measured for the SDSS sample. The small-scale clustering of our mock quasars is well-explained by central--satellite quasar pairs that reside in |$M_{\rm h}\gt 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$| dark matter haloes. For these pairs, satellite quasar luminosity is similar to that of central quasars. Our CLF models imply a relatively steep increase in the maximum satellite luminosity, |$L^*_{\mathrm{sat}}$|⁠, in haloes of |$M_{\rm h}\gt 10^{14}~\mathrm{M}_{\odot }\, h^{-1}$| with associated larger values of |$L^*_{\mathrm{sat}}$| at higher redshift. This leads to increase in the satellite fraction that manifests itself in an enhanced clustering signal at ≲1 Mpc  h −1. For the ongoing eBOSS-CORE sample, we predict ∼200–500 quasar pairs at z ∼ 1.5 (with |$M_{\rm h} \gtrsim 10^{13}~\mathrm{M}_{\odot }\, h^{-1}$| and |$M_{\rm bh} \gtrsim 10^{8}~\mathrm{M}_{\odot }\, h^{-1}$|⁠) at ∼25 kpc scales. Such a sample would be ≳ 10 times larger than current pair samples. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive intercomparison study investigating the radiometric performance of and concurrence among the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Landsat 8 Operational Land Imager (L8 OLI), and Landsat 9 OLI (L9 OLI) instruments. This study leverages data sourced from the Radiometric Calibration Network (RadCalNet) and focuses on spectral bands relevant for vegetation analysis and land cover classification, encompassing a thorough assessment of data quality, uncertainties, and underlying influencing factors. This study's outcomes underscore the efficacy of RadCalNet in evaluating the precision and reliability of remote sensing data, offering valuable insights into the strengths and limitations of ASTER, L8 OLI, and L9 OLI. These insights serve as a foundation for informed decision making in environmental monitoring and resource management, highlighting the pivotal role of RadCalNet in gauging the radiometric performance of remote sensing sensors. Results from RadCalNet sites, namely Railroad Valley Playa and Gobabeb, show their possible suitability for sensors with spatial resolutions down to 15 m. The results indicate that the measurements from both ASTER and OLI closely align with the data from RadCalNet, and the observed agreement falls comfortably within the total range of potential errors associated with the sensors and the test site information. [ABSTRACT FROM AUTHOR]

We present the analysis of the magnetic field (B -field) structure of galaxies measured with far-infrared (FIR) and radio (3 and 6 cm) polarimetric observations. We use the first data release of the Survey of extragALactic magnetiSm with SOFIA of 14 nearby ( < 20 Mpc) galaxies with resolved ( 5 ″ – 18 ″ ; 90 pc–1 kpc) imaging polarimetric observations using SOFIA/HAWC+ from 53 to 214 μ m. We compute the magnetic pitch-angle ( Ψ B ) profiles as a function of the galactocentric radius. We introduce a new magnetic alignment parameter (ζ) to estimate the disordered-to-ordered ratio of spiral B -fields. We find FIR and radio wavelengths to not generally trace the same B -field morphology in galaxies. The Ψ B profiles tend to be more ordered across all galactocentric radii in radio ( ζ 6 cm = 0.93 ± 0.03) than in FIR ( ζ 154 μ m = 0.84 ± 0.14). For spiral galaxies, FIR B -fields are 2%–75% more turbulent than the radio B -fields. For starburst galaxies, we find that FIR polarization is a better tracer of the B -fields along the galactic outflows than radio polarization. Our results suggest that the B -fields associated with dense, dusty, turbulent star-forming regions (those traced at FIR) are less ordered than warmer, less dense regions (those traced at radio) of the interstellar medium. The FIR B -fields seem to be more sensitive to the activity of the star-forming regions and molecular clouds within a vertical height of a few hundred parsecs in the disk of spiral galaxies than the radio B -fields. [ABSTRACT FROM AUTHOR]

We describe the data processing of the Survey on extragALactic magnetiSm with SOFIA (SALSA Legacy Program). This first data release presents 33% (51.34 hr out of 155.7 hr, including overheads) of the total awarded time from 2020 January to 2021 December. Our observations were performed using the newly implemented on-the-fly mapping (OTFMAP) technique in the polarimetric mode. We present the pipeline steps to obtain homogeneously reduced high-level data products of polarimetric maps of galaxies for use in scientific analysis. Our approach has a general design and can be applied to sources smaller than the field of view of the HAWC+ array in any given band. We estimate that the OTFMAP polarimetric mode offers a reduction of observing overheads by a factor 2.34 and an improvement in sensitivity by a factor 1.80 when compared to the same on-source time polarimetric observations using the chopping and nodding mode. The OTFMAP is a significant optimization of the polarimetric mode of HAWC+, as it ultimately reduces the cost of operations of HAWC+/SOFIA by increasing the science collected per hour of observation up to an overall factor of 2.49. The OTFMAP polarimetric mode is the standard observing strategy of SALSA. The results and quantitative analysis of this first data release are presented in Papers IV and V of the series. [ABSTRACT FROM AUTHOR]

The completed extended Baryon Oscillation Spectroscopic Survey (eBOSS) catalogues contain redshifts of 344 080 quasars at 0.8 < z < 2.2, 174 816 luminous red galaxies between 0.6 < z < 1.0, and 173 736 emission-line galaxies over 0.6 < z < 1.1 in order to constrain the expansion history of the Universe and the growth rate of structure through clustering measurements. Mechanical limitations of the fibre-fed spectrograph on the Sloan telescope prevent two fibres being placed closer than 62 arcsec in a single pass of the instrument. These 'fibre collisions' strongly correlate with the intrinsic clustering of targets and can bias measurements of the two-point correlation function resulting in a systematic error on the inferred values of the cosmological parameters. We combine the new techniques of pairwise-inverse probability and the angular upweighting (PIP+ANG) to correct the clustering measurements for the effect of fibre collisions. Using mock catalogues, we show that our corrections provide unbiased measurements, within data precision, of both the projected |$\rm {\mathit{ w}_p}\left(\mathit{ r}_p\right)$| and the redshift-space multipole ξ(ℓ = 0, 2, 4)(s) correlation functions down to |$0.1\, h^{-1}{\rm Mpc}$|⁠ , regardless of the tracer type. We apply the corrections to the eBOSS DR16 catalogues. We find that, on scales |$s\gtrsim 20\, h^{-1}{\rm Mpc}$| for ξℓ, as used to make baryon acoustic oscillation and large-scale redshift-space distortion measurements, approximate methods such as nearest-neighbour upweighting are sufficiently accurate given the statistical errors of the data. Using the PIP method, for the first time for a spectroscopic program of the Sloan Digital Sky Survey, we are able to successfully access the one-halo term in the clustering measurements down to |$\sim 0.1\, h^{-1}{\rm Mpc}$| scales. Our results will therefore allow studies that use the small-scale clustering to strengthen the constraints on both cosmological parameters and the halo occupation distribution models. [ABSTRACT FROM AUTHOR]