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We present a dynamical study of the intermediate polar cataclysmic variable YY Dra based on time-series observations in the $K$ band, where the donor star is known to be the major flux contributor. We covered the $3.97$-h orbital cycle with 44 spectra taken between $2020$ and $2022$ and two epochs of photometry observed in 2021 March and May. One of the light curves was simultaneously obtained with spectroscopy to better account for the effects of irradiation of the donor star and the presence of accretion light. From the spectroscopy, we derived the radial velocity curve of the donor star metallic absorption lines, constrained its spectral type to M0.5$-$M3.5 with no measurable changes in the effective temperature between the irradiated and non-irradiated hemispheres of the star, and measured its projected rotational velocity $v_\mathrm{rot} \sin i = 103 \pm 2 \, \mathrm{km}\,\mathrm{s}^{-1}$. Through simultaneous modelling of the radial velocity and light curves, we derived values for the radial velocity semi-amplitude of the donor star, $K_2 = 188^{+1}_{-2} \, \mathrm{km} \, \mathrm{s}^{-1}$, the donor to white dwarf mass ratio, $q=M_2/M_1 = 0.62 \pm 0.02$, and the orbital inclination, $i={42^{\circ}}^{+2^{\circ}}_{-1^{\circ}}$. These binary parameters yield dynamical masses of $M_{1} = 0.99^{+0.10}_{-0.09} \, \mathrm{M}_{\odot}$ and $M_2 = 0.62^{+0.07}_{-0.06} \, \mathrm{M}_{\odot}$ ($68$ per cent confidence level). As found for the intermediate polars GK Per and XY Ari, the white dwarf dynamical mass in YY Dra significantly differs from several estimates obtained by modelling the X-ray spectral continuum., Comment: 12 pages, 7 figures, 6 tables, accepted for publication in A&A

The spatial coherence wavefront outer scale (L_0) characterizes the size of the largest turbulence eddies in Earth's atmosphere, determining low spatial frequency perturbations in the wavefront of the light captured by ground-based telescopes. The motivation of this work is to introduce a novel technique for estimating L_0 from seeing-limited integral field spectroscopic (IFS) data. This approach is based on the impact of a finite L_0 on the light collected by the pupil entrance of a ground-based telescope. We take advantage of the homogeneity of IFS to generate band filter images spanning a wide wavelength range, enabling the assessment of image quality (IQ) at the telescope's focal plane. Comparing the measured wavelength-dependent IQ variation with predictions from Tokovinin (2002) analytical approach offers valuable insights into the prevailing L_0 parameter during the observations. We applied the proposed technique to observations from MUSE in the Wide Field Mode obtained at the Paranal Observatory. Our analysis successfully validates Tokovinin's analytical expression, which combines the seeing (E_0) and the L_0 parameters, to predict the IQ variations with the wavelength in ground-based astronomical data. However, we observed some discrepancies between the measured and predictions of the IQ that are analyzed in terms of uncertainties in the estimated E_0 and dome-induced turbulence contributions. This work constitutes the empirical validation of the analytical expression for estimating IQ at the focal plane of ground-based telescopes under specific E_0 and finite L_0 conditions. Additionally, we provide a simple methodology to characterize the L_0 and dome-seeing (E_d) as by-products of IFS observations routinely conducted at major ground-based astronomical observatories., Comment: 25 pages, 18 figures

The LIGO/Virgo detected a gravitational wave (GW) event, named GW200224_222234 (a.k.a. S200224ca) and classified as a binary-black-hole coalescence, on February 24, 2020. Given its relatively small localization skymap (71 deg$^2$ for a 90% credible region; revised to 50 deg$^2$ in GWTC-3), we performed target-of-opportunity observations using the Subaru/Hyper Suprime-Cam (HSC) in the $r2$- and $z$-bands. Observations were conducted on February 25 and 28 and March 23, 2020, with the first epoch beginning 12.3 h after the GW detection. The survey covered the highest probability sky area of 56.6 deg$^2$, corresponding to a 91% probability. This was the first deep follow-up ($m_{r}\gtrsim24, m_{z}\gtrsim23$) for a binary-black-hole merger covering $>$90% of the localization. By performing image subtraction and candidate screening including light curve fitting with transient templates and examples, we found 22 off-nucleus transients that were not ruled out as the counterparts of GW200224_222234 with only our Subaru/HSC data. We also performed GTC/OSIRIS spectroscopy of the probable host galaxies for five candidates; two are likely to be located within the 3D skymap, whereas the others are not. In conclusion, 19 transients remain as possible optical counterparts of GW200224_222234; however, we could not identify a unique promising counterpart. If there are no counterparts in the remaining candidates, the upper limits of optical luminosity are $\nu L_{\nu} < 5.2^{+2.4}_{-1.9}\times 10^{41}$ erg s$^{-1}$ and $\nu L_{\nu} < 1.8^{+0.8}_{-0.6}\times 10^{42}$ erg s$^{-1}$ in the $r2$- and $z$-bands, respectively, at $\sim$12 h after GW detection. We also discuss improvements in the strategies of optical follow-ups for future GW events., Comment: 22 pages, 15 figures. Accepted for publication in the Astrophysical Journal

The bright-rimmed cloud IC 1396N is believed to host one of the few known cases where two bipolar CO outflows driven by young stellar objects actually collide. The CO outflows are traced by chains of knots of H_2 emission, with enhanced emission at the position of the possible collision. The aim of this work is to use the proper motions of the H_2 knots to confirm the collision scenario. A second epoch H_2 image was obtained, and the proper motions of the knots were determined with a time baseline of ~11 years. We also performed differential photometry on the images to check the flux variability of the knots. For each outflow (N and S) we classified the knots as pre-collision or post-collision. The axes of the pre-collision knots, the position of the possible collision point, and the axes of the post-collision knots were estimated. The difference between the proper motion direction of the post-collision knots and the position angle from the collision point was also calculated. For some of the knots we obtained the 3D velocity by using the radial velocity derived from H_2 spectra. The velocity pattern of the H_2 knots in the area of interaction (post-collision knots) shows a deviation from that of the pre-collision knots, consistent with being a consequence of the interaction between the two outflows. This favours the interpretation of the IC 1396N outflows as a true collision between two protostellar jets instead of a projection effect., Comment: Accepted by A&A; 10 pages, 6 figures

Interstellar dust grain alignment causes polarization from UV to mm wavelengths, allowing the study of the geometry and strength of the magnetic field. Over last couple of decades observations and theory have led to the establishment of the Radiative Alignment Torque (RAT) mechanism as leading candidate to explain the effect. With a quantitatively well constrained theory, polarization can be used not only to study the interstellar magnetic field, but also the dust and other environmental parameters. Photo-dissociation Regions (PDRs), with their intense, anisotropic radiation fields, consequent rapid $\rm H_{2}$ formation, and high spatial density-contrast provide a rich environment for such studies. Here we discuss an expanded optical, NIR, and mm-wave study of the IC\,63 nebula, showing strong $\rm H_{2}$ formation-enhanced alignment and the first direct empirical evidence for disalignment due to gas-grain collisions using high-resolution $\rm HCO^{+}$(J=1-0) observations. We find that relative amount of polarization is marginally anti-correlated with column density of $\rm HCO^{+}$. However, separating the lines of sight of optical polarimetry into those behind, or in front of, a dense clump as seen from $\gamma$ Cas, the distribution separates into two well defined sets, with data corresponding to \enquote{shaded} gas having a shallower slope. This is expected if the decrease in polarization is caused by collisions since collisional disalignment rate is proportional to R$_C\propto n\sqrt{T}$. Ratios of the best-fit slopes for the \enquote{illuminated} and \enquote{shaded} samples of lines of sight agrees, within the uncertainties, with the square-root of the two-temperature H$_2$ excitation in the nebula seen by Thi et al. (2009)., Comment: 14 pages, 6 figures, Accepted for publication in ApJ

Based on new near-infrared spectroscopic data from the instrument EMIR on the 10.4 m Gran Telescopio Canarias (GTC) we report the presence of an ionized and warm molecular outflow in the luminous type-2 quasar J150904.22+043441.8 (z = 0.1118). The ionized outflow is faster than its molecular counterpart, although the outflow sizes that we derive for them are consistent within the errors (1.34$\pm$0.18 kpc and 1.46$\pm$0.20 kpc respectively). We use these radii, the broad emission-line luminosities and in the case of the ionized outflow, the density calculated from the trans-auroral [OII] and [SII] lines, to derive mass outflow rates and kinetic coupling efficiencies. Whilst the ionized and warm molecular outflows represent a small fraction of the AGN power ($\leq$0.033% and 0.0001% of L$_{bol}$ respectively), the total molecular outflow, whose mass is estimated from an assumed warm-to-cold gas mass ratio of 6$\times10^{-5}$, has a kinetic coupling efficiency of $\sim$1.7%L$_{bol}$. Despite the large uncertainty, this molecular outflow represents a significant fraction of L$_{bol}$ and it could potentially have a significant impact on the host galaxy. In addition, the quasar spectrum reveals bright and patchy narrow Pa$\alpha$ emission extending out to 4 arcsec (8 kpc) South-East and North-West from the active nucleus., Comment: 6 pages, 4 figures, accepted for publication in MNRAS Letters

The detection of gamma-ray emission from narrow-line Seyfert 1 galaxies (NLSy1) has challenged the idea that large black hole (BH) masses ($\ge$10$^8$ M$_{\odot}$) are needed to launch relativistic jets. We present near-infrared imaging data of the gamma-ray-emitting NLSy1 PKS 1502+036 obtained with the Very Large Telescope. Its surface brightness profile, extending to $\sim$ 20 kpc, is well described by the combination of a nuclear component and a bulge with a Sersic index $n$ = 3.5, which is indicative of an elliptical galaxy. A circumnuclear structure observed near PKS 1502+036 may be the result of galaxy interactions. A BH mass of about $\sim 7 \times 10^{8}$ M$_{\odot}$ has been estimated by the bulge luminosity. The presence of an additional faint disc component cannot be ruled out with the present data, but this would reduce the BH mass estimate by only $\sim$ 30%. These results, together with analogous findings obtained for FBQS J1644+2619, indicate that the relativistic jets in gamma-ray-emitting NLSy1 are likely produced by massive black holes at the center of elliptical galaxies., Comment: 5 pages, 2 figures, 1 table, and 2 supplementary figures. Monthly Notices of the Royal Astronomical Society Letters, Volume 478, Issue 1, L66-L71

The discovery of $\gamma$-ray emission from radio-loud narrow-line Seyfert 1 (NLSy1) galaxies has questioned the need for large black hole masses (> 10$^8$ M$_{\odot}$) to launch relativistic jets. We present near-infrared data of the $\gamma$-ray-emitting NLSy1 FBQS J1644+2619 that were collected using the camera CIRCE (Canarias InfraRed Camera Experiment) at the 10.4-m Gran Telescopio Canarias to investigate the structural properties of its host galaxy and to infer the black hole mass. The 2D surface brightness profile is modelled by the combination of a nuclear and a bulge component with a S\'ersic profile with index $n$ = 3.7, indicative of an elliptical galaxy. The structural parameters of the host are consistent with the correlations of effective radius and surface brightness against absolute magnitude measured for elliptical galaxies. From the bulge luminosity, we estimated a black hole mass of (2.1$\pm$0.2) $\times$10$^8$ M$_{\odot}$, consistent with the values characterizing radio-loud active galactic nuclei., Comment: 5 pages, 3 figures, 1 table. Monthly Notices of the Royal Astronomical Society Letter, Vol. 469, L11-L15

FRIDA is a diffraction-limited imager and integral-field spectrometer that is being built for the adaptive-optics focus of the Gran Telescopio Canarias. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode spectral resolutions of 1500, 4000 and 30,000. FRIDA is starting systems integration and is scheduled to complete fully integrated system tests at the laboratory by the end of 2017 and to be delivered to GTC shortly thereafter. In this contribution we present a summary of its design, fabrication, current status and potential scientific applications., Comment: To appear in the proceedings of SPIE conference 9908 "Ground-based and Airborne Instrumentation for Astronomy VI". 8 pages

In order to probe the inside-out formation of the most massive galaxies in the Universe, we have explored the radial (0.1 < R < 8 kpc) variation of the spectral energy distribution (SED) of M87 from UV to IR. For this purpose, we have combined high resolution data in 16 different bands. Our analysis indicate that the age of the stellar population of M87 remains almost unchanged with radius. However, the metallicity ([Z/H]) profile presents three different zones: the innermost kpc shows a plateau with supersolar metallicity, followed by a decline in metallicity down to 5 kpc and another plateau afterwards. The size of the inner plateau is similar to the expected size (Re) of an object with the predicted mass of M87 at z=2. The global [Z/H] gradient is -0.26 +- 0.10, similar to those found in other nearby massive ellipticals. The observed change in the stellar population of M87 is consistent with a rapid formation of the central part (R<5 kpc) of this galaxy followed by the accretion of the outer regions through the infall of more metal-poor material., Comment: Accepted in MNRAS

We present a near-infrared spectroscopic study of a stellar mass selected sample of galaxies at z~1 utilising the LIRIS multi-object spectrograph on the WHT. We detect continuum, and the H alpha line for our sample, which is one of the better direct tracers of star formation in external galaxies. We spectroscopically measure the H alpha emission from 41 massive (M_{*}>10^{10.5} Msol) galaxies taken from the POWIR Survey with spectroscopic redshifts 0.410^{11} Msol which are detected in H alpha emission at z<0.9. We furthermore find that the fraction of galaxies with H alpha emission drops steadily and significantly with redder (U-B) colours at z~1, and that the SSFR drops with increasing (U-B) colour for galaxies at all masses. By investigating the SFR-mass relation we find that the SFR is roughly constant with mass, in possible contrast to previous work, and that the specific star formation rate (SSFR) is lower in the most massive galaxies. The scatter in the SFR vs. mass relationship is very small for those systems with ongoing star formation which suggests that star formation in the most massive galaxies at z~1 shuts off rather abruptly over <1 Gyr, without an obvious gradual decline. We furthermore investigate the SFR as a function of (U-B) colour divided into different mass bins, revealing a tracer of the epoch of transition from star forming to passive, as a form of star formation "downsizing". This suggests that the shut off of star formation occurs before the change in a galaxy's colour. We find that galaxy stellar mass is the primary driving mechanisms behind the star formation history for these galaxies and discuss several possible mechanisms for regulating this process., Comment: 20 pages, accepted for publication in MNRAS

EX Lup is the prototype of the EXor class of eruptive young stars. These objects show optical outbursts which are thought to be related to runaway accretion onto the star. In a previous study we observed in-situ crystal formation in the disk of EX Lup during its latest outburst in 2008, making the object an ideal laboratory to investigate circumstellar crystal formation and transport. This outburst was monitored by a campaign of ground-based and Spitzer Space Telescope observations. Here we modeled the spectral energy distribution of EX Lup in the outburst from optical to millimeter wavelengths with a 2D radiative transfer code. Our results showed that the shape of the SED at optical wavelengths was more consistent with a single temperature blackbody than a temperature distribution. We also found that this single temperature component emitted 80-100 % of the total accretion luminosity. We concluded that a thermal instability, the most widely accepted model of EXor outbursts, was likely not the triggering mechanism of the 2008 outburst of EX Lup. Our mid-infrared Spitzer spectra revealed that the strength of all crystalline bands between 8 and 30 um increased right after the end of the outburst. Six months later, however, the crystallinity in the 10 um silicate feature complex decreased. Our modeling of the mid-infrared spectral evolution of EXLup showed that, although vertical mixing should be stronger during the outburst than in the quiescent phase, fast radial transport of crystals (e.g., by stellar/disk wind) was required to reproduce the observed mid-infrared spectra., Comment: Accepted for publication in ApJ, 37 pages, 11 figures, 2 tables

We performed J- and R-band linear polarimetry with the 4.2 m William Herschel Telescope at the Observatorio del Roque de los Muchachos and with the 1.6 m telescope at the Observat\'orio do Pico dos Dias, respectively, to derive the magnetic field geometry of the diffuse molecular cloud surrounding the embedded protostellar system NGC 1333 IRAS 4A. We obtained interstellar polarization data for about two dozen stars. The distribution of polarization position angles has low dispersion and suggests the existence of an ordered magnetic field component at physical scales larger than the protostar. Some of the observed stars present intrinsic polarization and evidence of being young stellar objects. The estimated mean orientation of the interstellar magnetic field as derived from these data is almost perpendicular to the main direction of the magnetic field associated with the dense molecular envelope around IRAS 4A. Since the distribution of the CO emission in NGC 1333 indicates that the diffuse molecular gas has a multi-layered structure, we suggest that the observed polarization position angles are caused by the superposed projection along the line of sight of different magnetic field components., Comment: 37 pages, 9 figures, 5 tables, accepted for publication in AJ

Very Large Telescope adaptive optics images of NGC 253 with resolutions down to 200 mas resolve the central 300 pc of this galaxy in ~ 37 infrared (IR) bright knots, a factor of 3 larger than previously reported, and extended diffuse emission. The angular resolution, comparable to that of available Very Large Array 2 cm maps, permits us a very accurate IR-radio registration. Eight radio sources are found to have an IR counterpart. The knots have H\alpha equivalent width of about 80 angstroms, sizes of ~ 3 pc, magnitudes in L-band of about 12 mag and relatively high extinction, Av ~ 7 mag. Their spectral energy distributions (SEDs) look very similar, characterized by a maximum at 20 micron and a gentle bump in the 1 - 2 micron range. These features can be well reproduced by considering an important contribution of very young stellar objects to the IR, efficiently heating their dust envelope. The evidence indicates that these are young massive clusters bursting from their dust cocoons. A median SED of the knots is provided, which may represent one of the most genuine templates of an extragalactic circumnuclear star-forming region. The lack of any optical or IR counterpart for the previously identified radio core calls into question its supposed active nucleus nature. This source may instead represent a scaled up version of Sgr A* at the Galactic Centre., Comment: 5 pages, 3 figures. Accepted for publication in MNRAS (Letters)

In this letter we present clear evidence that Mrk 573 is an obscured Narrow-Line Seyfert 1 (NLSy1) and not an archetypal Seyfert 2, as it has been classified until now. Only three galaxies have been proposed as members of this class, prior to this work. Here we report near-infrared spectroscopic data taken with LIRIS on the 4.2 m William Herschel Telescope (WHT). Our high quality near-infrared nuclear spectrum in the 0.88-1.35 micron wavelength range shows the permitted O I 1.128,1.317 micron narrow lines, the Fe II 9200-\AA lines and the Fe II 1-micron lines, together with a relatively broad component (~1700 km/s) of Paschen Beta. These features can originate only in an optically thick high density region, similar to those observed in the Broad Line Region (BLR)., Comment: 12 pages, 4 figures, accepted for publication in ApJ Letters

We present mid-infrared data of a sample of 57 AGNs obtained with the instrument ISOCAM on board the satellite ISO. The images were obtained through the LW2 (6.75 microns) and LW7 (9.62 microns) filters. This is a new analysis of Clavel et al. (2000) galaxy sample, which is divided into 26 type 1 (< or = 1.5) and 28 type 2 (> 1.5) Seyfert galaxies, plus three QSOs. The spatial resolution of the images allow us to separate the nuclear and the extended contributions to the total emission after decomposing the brightness profiles into different morphological components. The most common components are a central point source (identified as the active nucleus) and an exponential disk. In some cases a bulge, a bar or a ring are needed. The relative contribution of the nucleus to the total emission appears larger in Seyfert 1 than in Seyfert 2. This result confirms that both types of Seyfert galaxies are different in the mid-infrared and supports the existence of an structure which produces anisotropic emission in this wavelength range. We have also explored correlations between the mid-infrared and the radio and X-ray wavelength ranges. The well established radio/infrared correlation is mantained in our sample for the global emission of the galaxies. If only the nuclear infrared emission is considered then a non-linear correlation is apparent in the luminosity-luminosity scatter diagram. The ratio between the intrinsic hard X-ray and the nuclear mid-infrared emission presents large scatter and slightly larger values for type 2 Seyfert galaxies. These results seem to be consistent with the presence of a clumpy dusty torus surrounding the active nucleus., Comment: 28 pages, 10 figures, 3 tables. Published in AJ. Erratum added, 2 pages, 1 figure, accepted by AJ

We present preliminary results of H_alpha near-infrared spectroscopy of six galaxies with redshifts z ~ 1 drawn from the DEEP2 Galaxy Redshift Survey. The spectra have been taken with the multi-slit mode of LIRIS (Long-slit Intermediate Resolution Infrared Spectrograph) installed at the 4.2-m William Herschel Telescope. This is a pilot study for a larger program to obtain H_alpha luminosities of about 50 star-forming galaxies at z ~ 1, with the aim of deriving the corresponding star formation rates (SFRs) from H_alpha as well as studying the relationship with other SFR indicators. The new galaxy sample will be selected from the Extended Groth Strip Survey, where galaxies will also have measures of stellar masses, reddening, far-IR data, and galaxy morphologies., Comment: 5 pages, 2 figures, uses asp2004.sty. To appear in the proceedings of the Spitzer Conference "Infrared Diagnostics of Galaxy Evolution", Pasadena, CA, 14-16 November 2005, ed. R. Chary

The photoionization of extended narrow-line regions in Seyfert galaxies by the radiation produced in a thick accretion disk is studied. The emission-line spectrum is calculated for a range of black hole masses, varying the values of the ionization parameter and the disk size. It is found that models with a million solar masses fit observations of very large accretion disk sizes, while models with 10 million solar masses fit them better with smaller disks. The latter models are preferable since they have lower super-Eddington accretion rates.