Low luminosity TypeII supernovae-II. Pointing towards moderate mass precursors

We present new data for five under-luminous type II-plateau supernovae (SNe IIP), namely SN 1999gn, SN 2002gd, SN 2003Z, SN 2004eg and SN 2006ov. This new sample of low-luminosity SNe IIP (LL SNe IIP) is analyzed together with similar objects studied in the past. All of them show a flat light curve plateau lasting about 100 days, an under luminous late-time exponential tail, intrinsic colours that are unusually red, and spectra showing prominent and narrow P-Cygni lines. A velocity of the ejected material below 10^3 km/s is inferred from measurements at the end of the plateau. The 56Ni masses ejected in the explosion are very small (less than 10^-2 solar masses). We investigate the correlations among 56Ni mass, expansion velocity of the ejecta and absolute magnitude in the middle of the plateau, confirming the main findings of Hamuy (2003), according to which events showing brighter plateau and larger expansion velocities are expected to produce more 56Ni. We propose that these faint objects represent the low luminosity tail of a continuous distribution in parameters space of SNe IIP. The physical properties of the progenitors at the explosion are estimated through the hydrodynamical modeling of the observables for two representative events of this class, namely SN 2005cs and SN 2008in. We find that the majority of LL SNe IIP, and quite possibly all, originate in the core-collapse of intermediate mass stars, in the mass range 10-15 solar masses.Comment: 20 pages, 19 figures, accepted for publication in MNRA

Low luminosity Type II supernovae - II. Pointing towards moderate mass precursors

We present new data for five underluminous Type II-plateau supernovae (SNe IIP), namely SN 1999gn, SN 2002gd, SN 2003Z, SN 2004eg and SN 2006ov. This new sample of low-luminosity SNe IIP (LL SNe IIP) is analysed together with similar objects studied in the past. All of them show a flat light-curve plateau lasting about 100 d, an underluminous late-time exponential tail, intrinsic colours that are unusually red, and spectra showing prominent and narrow P Cygni lines. A velocity of the ejected material below 10(3) km s(-1) is inferred from measurements at the end of the plateau. The Ni-56 masses ejected in the explosion are very small (&lt; 10(-2) M-circle dot). We investigate the correlations among Ni-56 mass, expansion velocity of the ejecta and absolute magnitude in the middle of the plateau, confirming the main findings of Hamuy, according to which events showing brighter plateau and larger expansion velocities are expected to produce more Ni-56. We propose that these faint objects represent the LL tail of a continuous distribution in parameters space of SNe IIP. The physical properties of the progenitors at the explosion are estimated through the hydrodynamical modelling of the observables for two representative events of this class, namely SN 2005cs and SN 2008in. We find that the majority of LL SNe IIP, and quite possibly all, originate in the core collapse of intermediate-mass stars, in the mass range 10-15 M-circle dot.</p

The Enhanced Resolution Imager and Spectrograph for the VLT

ERIS, the Enhanced Resolution Imager and Spectrograph, is an instrument that both extends and enhances the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It replaces two instruments that were being maintained beyond their operational lifetimes, combines their functionality on a single focus, provides a new wavefront sensing module for natural and laser guide stars that makes use of the Adaptive Optics Facility, and considerably improves on their performance. The observational modes ERIS provides are integral field spectroscopy at 1-2.5 {\mu}m, imaging at 1-5 {\mu}m with several options for high contrast imaging, and longslit spectroscopy at 3-4 {\mu}m, The instrument is installed at the Cassegrain focus of UT4 at the VLT and, following its commissioning during 2022, has been made available to the community.Comment: 19 pages with 29 figures; submitted to A&

Search for global oscillations on Jupiter with a double-cell sodium magneto-optical filter

Doppler observations on Jupiter are presented and discussed. A two-cells Magneto-Optical Filter (MOF), able to obtain two separate signals, Red and Blue, on the opposite wings of the Sodium D-lines, along with a continuum reference signal, has been used. This set of data permits to discriminate between real oscillations and albedo "modes" by means of the two algorithms ${\cal D}=(B-R)/(B+R)$ and ${\cal S}=(B+R)$/conti nuum. No unambiguous oscillation modes were detected with amplitudes above the 1-σ level of ~1.2 m s-1 in the range between 0.5 and 0.7 mHz. However, using refined analysis for signal recovery in a noisy background we notice an increase of power also in the region of the solar 5 min oscillations. The albedo variations on the Jupiter's surface and instrumental effects are addressed to be responsible for the spurious signals

Control system architecture for AMICA: The Antarctic NIR/MIR camera for IRAIT

The IRAIT project is aimed at preparing the first permanent observatory, a 80 cm class telescope, at Dome C, a site located at 3200 height on the Antarctic plateau. To exploit the high-quality and low-sky-background conditions offered by the site in spectral regions beyond 20 um, IRAIT telescope will be equipped at its Nasmyth focus by a dual feed infrared camera: a near/medium infrared camera (AMIGA) designed to be operated by a Si:As detector array sensitivity in the range 5-28 μm, and a In:Sb detector array covering the shorter spectral range down to J band. AMICA is a joint effort of several Italian institutions (OAMI, OATO, OAPD) led by the Teramo Observatory, belonging to Istituto Nazionale di Astrofisica (INAF). The importance of this instrument is twofold: AMICA is expected to provide extensive surveys of the southern sky in K,L,M,N and Q bands, and to give a direct estimate of the observational quality of this highly promising site. To face the prohibitive Antarctic environment, the telescope should be fully robotic and operations for the telescope and its instrumentation remotely controlled. Careful consideration is to be devoted to the design and integration of the control system, besides the accurate insulation for all the equipment. In the present paper we will provide an overview of the AMICA camera focused on the detectors control electronics, the solutions adopted to reduce the impact with a severe environment and the present status of the project

AMICA: the Antarctic Mid-Infrared CAmera for the IRAIT telescope

We report a preliminary study of the main focal plane instrument for the IRAIT telescope, currently being built at INAF-Astronomical Observatory of Teramo. The basic requirements are those of a remotely-controlled camera aimed to perform 10- and 20-μm photometry from Dome-C in the standard bandpasses N and Q. Starting from the site properties and the science goals, the main components of AMICA (Antarctic Mid-Infrared CAmera) are described: a Si:As BIB array detector, sensitive in the range 2–28 μm; a fully reflective optical design; a cryostat modified in order to work at the extreme environmental conditions of the antarctic plateau; a cryocooler maintaining the operating temperature of 4.2 K without external intervention; an automatized and flexible control electronics.
AMICA is designed to fully exploit the unique mid-infrared observing conditions at Dome-C

AMICA Control System Progress Status

The Antarctic Multi-band Infrared Camera is a NIR/MIR double armed camera operating in the K, L, M, N, Q photometrical bands that will be mounted at one of the F/21.65 IRAIT Nasmyth foci (Tosti et al. 2006; Dolci et al. 2009). AMICA will host two detectors: the short wavelength radiation, 1-5.5 µm NIR band, is sensed by a Raytheon CRC-463 InSb 256 × 256 detector, while the long wavelengths 7-25 µm MIR band – is served by a DRS Technologies BIB Si:As 128 × 128 pixels array optimized for moderate photon flux. A fully reflective optical system, composed of two off-axis parabolic mirrors and one fixed 45° flat mirror, achieves a common, optimized, focal ratio reduction to F/14.73 at the detectors focal plane. Taking advantage from the large difference in pixel size between the NIR/MIR detectors, the resulting field-of-view will be 2.29 × 2.29 arcmin2 and 2.87 × 2.87 arcmin2 on the NIR and MIR array, respectively. In the present paper we report on the successful tests of the NIR/ MIR multiplexers functionality at the maximum required readout frequency

Status of the amica project: ready for the antarctic adventure

The status of the AMICA project is reported. Final tests are currently running at Teramo Observatory before moving the instrument to Antarctica. AMICA is a camera equipped with two array detectors to perform astronomical imaging in the 2–28 μm band. It will be mounted at the IRAIT focal plane. Its very special feature is the antarctic operability. AMICA subsystems have been tested at typical antarctic conditions, in order to adopt technological solutions that ensure the correct operation of AMICA even on the antarctic plateau. Moreover, since human operations are not possible during the antarctic “winter", AMICA has been designed to operate in a completely automatic mode. AMICA is essentially aimed to demonstrate the potential of Antarctica for Infrared Astronomy and should therefore produce significant data, both for astronomy and site-testing. In addition, the experience gained in its technological development will be useful for building future astronomical instruments for extreme environment sites

AMICA: The First camera for Near- and Mid-Infrared Astronomical Imaging at Dome C

AMICA (Antarctic Multiband Infrared CAmera) is an instrument designed to perform astronomical imaging in the near- (1-5 μm) and mid- (5–27 μm) infrared wavelength regions. Equipped with two detectors, an InSb 2562 and a Si:As 1282 IBC, cooled at 35 and 7 K respectively, it will be the first instrument to investigate the potential of the Italian-French base Concordia for IR astronomy. The main technical challenge is represented by the extreme conditions of Dome C (T ~ -90 °C, p ~ 640 mbar). An environmental control system ensures the correct start-up, shut-down and housekeeping of the various components of the camera. AMICA will be mounted on the IRAIT telescope and will perform survey-mode observations in the Southern sky. The first task is to provide important site-quality data. Substantial contributions to the solution of fundamental astrophysical quests, such as those related to late phases of stellar evolution and to star formation processes, are also expected

LIGO/Virgo S200224ca: GRAWITA-Campo Imperatore observations

We carried out observations of the LIGO/Virgo trigger GW S200224ca (GCN Circ. #27184) using the INAF-OAAb 0.9m Schmidt Telescope of the INAF - Astronomical Observatory of Abruzzo located at 2150 meters o.s.l. at Campo Imperatore (Italy) and equipped with a 4096x4096 CCD covering a field of view of 1.15×1.15 square degrees. Due to weather conditions, only three pointings were made covering an area of nearly 4 square degrees; a containment probability of ~ 8 % of the 50% credible region was captured. The pointing sequence was generated using the GWsky script (G. Greco, https://github.com/ggreco77/GWsky), starting from the high probability region of the bayestar skymap and taking into account the airmass and relative density of nearby galaxies at the distance of 1585 +/- 331 Mpc. The total exposure time for each image was 3x180 sec. The observations were taken with the r-Sloan band on 2020-02-24 starting at 23:47:37.0 UT, about one hour after the GW detection (i.e. 2020-02-24 22:22:34.406 UTC). The estimated limiting magnitude in r-Sloan is about 21.5 mag. Hereafter the log of the observations. | RA (J2000) | Dec (J2000) | UT time | filter | exposure time| | 11:43:50.29 | -07:49:10 | 2020-02-24T23:47:37.0 | r-sloan | 3x180 sec | | 11:35:44.35 | -07:49:10 | 2020-02-25T00:04:09.6 | r-sloan | 3x180 sec | | 11:39:47.98 | -07:49:35 | 2020-02-25T00:20:44.8 | r-sloan | 3x180 sec | The analysis of images is ongoing. -------------------------------------------- De Luise Fiore, PhD INAF - Osservatorio Astronomico d'Abruzzo Via Mentore Maggini, s.n.c. 64100 - TERAMO Tel +39-0861-439712 Fax +39-0861-439740 -------------------------------------------