A. Di Marco - Univ. Roma Tor Vergata and INFN Roma Tor Vergata

A. Di Marco
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Name
A. Di Marco
Affiliation
Univ. Roma Tor Vergata and INFN Roma Tor Vergata
City
Roma
Country
Italy

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Solar and Stellar Astrophysics (15)
 
Astrophysics of Galaxies (15)
 
High Energy Physics - Experiment (8)
 
Nuclear Experiment (8)
 
High Energy Physics - Phenomenology (7)
 
Cosmology and Nongalactic Astrophysics (5)
 
Physics - Instrumentation and Detectors (5)
 
Physics - Mesoscopic Systems and Quantum Hall Effect (3)
 
Computer Science - Robotics (3)
 
Computer Science - Learning (3)
 
High Energy Astrophysical Phenomena (3)
 
Quantitative Biology - Genomics (2)
 
High Energy Physics - Theory (2)
 
Quantitative Biology - Populations and Evolution (2)
 
Instrumentation and Methods for Astrophysics (1)
 
Nuclear Theory (1)
 
Computer Science - Performance (1)
 
Computer Science - Cryptography and Security (1)
 
General Relativity and Quantum Cosmology (1)
 
Statistics - Machine Learning (1)
 
Mathematics - Dynamical Systems (1)
 
Physics - Superconductivity (1)
 
Computer Science - Software Engineering (1)

Publications Authored By A. Di Marco

2017Apr
Authors: C. Burigana, C. S. Carvalho, T. Trombetti, A. Notari, M. Quartin, G. De Gasperis, A. Buzzelli, N. Vittorio, G. De Zotti, P. de Bernardis, J. Chluba, M. Bilicki, L. Danese, J. Delabrouille, L. Toffolatti, A. Lapi, M. Negrello, P. Mazzotta, D. Scott, D. Contreras, A. Achucarro, P. Ade, R. Allison, M. Ashdown, M. Ballardini, A. J. Banday, R. Banerji, J. Bartlett, N. Bartolo, S. Basak, M. Bersanelli, A. Bonaldi, M. Bonato, J. Borrill, F. Bouchet, F. Boulanger, T. Brinckmann, M. Bucher, P. Cabella, Z. -Y. Cai, M. Calvo, G. Castellano, A. Challinor, S. Clesse, I. Colantoni, A. Coppolecchia, M. Crook, G. D'Alessandro, J. -M. Diego, A. Di Marco, E. Di Valentino, J. Errard, S. Feeney, R. Fernandez-Cobos, S. Ferraro, F. Finelli, F. Forastieri, S. Galli, R. Genova-Santos, M. Gerbino, J. Gonzalez-Nuevo, S. Grandis, J. Greenslade, S. Hagstotz, S. Hanany, W. Handley, C. Hernandez-Monteagudo, C. Hervias-Caimapo, M. Hills, E. Hivon, K. Kiiveri, T. Kisner, T. Kitching, M. Kunz, H. Kurki-Suonio, L. Lamagna, A. Lasenby, M. Lattanzi, J. Lesgourgues, M. Liguori, V. Lindholm, M. Lopez-Caniego, G. Luzzi, B. Maffei, N. Mandolesi, E. Martinez-Gonzalez, C. J. A. P. Martins, S. Masi, D. McCarthy, A. Melchiorri, J. -B. Melin, D. Molinari, A. Monfardini, P. Natoli, A. Paiella, D. Paoletti, G. Patanchon, M. Piat, G. Pisano, L. Polastri, G. Polenta, A. Pollo, V. Poulin, M. Remazeilles, M. Roman, J. -A. Rubino-Martin, L. Salvati, A. Tartari, M. Tomasi, D. Tramonte, N. Trappe, C. Tucker, J. Valiviita, R. Van de Weijgaert, B. van Tent, V. Vennin, P. Vielva, K. Young, M. Zannoni, for the CORE Collaboration

We discuss the effects on the CMB, CIB, and thermal SZ effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. We investigate the scientific perspectives opened by future CMB space missions, focussing on the CORE proposal. The improvements in sensitivity offered by a mission like CORE, together with its high resolution over a wide frequency range, will provide a more accurate estimate of the CMB dipole. Read More

We present constraints on the reheating era within the string Fibre Inflation scenario, in terms of the effective equation-of-state parameter of the reheating fluid, $w_{reh}$. The results of the analysis, completely independent on the details of the inflaton physics around the vacuum, illustrate the behavior of the number of $e$-foldings during the reheating stage, $N_{reh}$, and of the final reheating temperature, $T_{reh}$, as functions of the scalar spectral index, $n_s$. We analyze our results with respect to the current bounds given by the PLANCK mission data and to upcoming cosmological experiments. Read More

NGC 6067 is a young open cluster hosting the largest population of evolved stars among known Milky Way clusters in the 50-150 Ma age range. It thus represents the best laboratory in our Galaxy to constrain the evolutionary tracks of 5-7 M$_{\odot}$ stars. We have used high-resolution spectra of a large sample of bright cluster members (45), combined with archival photometry, to obtain accurate parameters for the cluster as well as stellar atmospheric parameters. Read More

In this paper, we apply reconstruction techniques to recover the potential parameters for a particular class of single-field models, the $\alpha$-attractor (supergravity) models of inflation. This also allows to derive the inflaton vacuum expectation value at horizon crossing. We show how to use this value as one of the input variables to constrain the postaccelerated inflationary phase. Read More

PID control architectures are widely used in industrial applications. Despite their low number of open parameters, tuning multiple, coupled PID controllers can become tedious in practice. In this paper, we extend PILCO, a model-based policy search framework, to automatically tune multivariate PID controllers purely based on data observed on an otherwise unknown system. Read More

In practice, the parameters of control policies are often tuned manually. This is time-consuming and frustrating. Reinforcement learning is a promising alternative that aims to automate this process, yet often requires too many experiments to be practical. Read More

The X-ray binary population of the Small Magellanic Cloud (SMC) contains a large number of massive X-ray binaries and the recent survey of the SMC by XMM-Newton has resulted in almost 50 more tentative high mass X-ray binary candidates. Using probability parameters from Haberl & Sturm (2016) together with the optical spectra and timing in this work, we confirm six new massive X-ray binaries in the SMC. We also report two very probable binary periods; of 36. Read More

NGC 7067 is a young open cluster located in the direction between the first and the second Galactic quadrants and close to the Perseus spiral arm. This makes it useful for studies of the nature of the Milky Way spiral arms. Stromgren photometry taken with the Wide Field Camera at the Isaac Newton Telescope allowed us to compute individual physical parameters for the observed stars and hence to derive cluster's physical parameters. Read More

2016Dec
Affiliations: 1Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 2Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 3Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 4Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 5Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 6Univ. Roma and INFN Roma, 7Univ. Roma and INFN Roma, 8INFN LNGS, 9INFN LNGS, 10INFN LNGS, 11IHEP Beijing, 12IHEP Beijing, 13IHEP Beijing, 14IHEP Beijing, 15IHEP Beijing, 16IHEP Beijing, 17IHEP Beijing

The DAMA/LIBRA experiment ($\sim$ 250 kg of highly radio-pure NaI(Tl)) is running deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F. Read More

2016Nov
Affiliations: 1University of Alicante, University of Florida, 2University of Alicante

The open cluster Berkeley 90 is the home to one of the most massive binary systems in the Galaxy, LS III +46$^{\circ}$11, formed by two identical, very massive stars (O3.5 If* + O3.5 If*), and a second early-O system (LS III +46$^{\circ}$12 with an O4. Read More

This paper proposes an automatic controller tuning framework based on linear optimal control combined with Bayesian optimization. With this framework, an initial set of controller gains is automatically improved according to a pre-defined performance objective evaluated from experimental data. The underlying Bayesian optimization algorithm is Entropy Search, which represents the latent objective as a Gaussian process and constructs an explicit belief over the location of the objective minimum. Read More

On the basis of the Galactic O-Star Spectroscopic Survey (GOSSS), a detailed systematic investigation of the O Vz stars is presented. The currently used spectral classification criteria are rediscussed, and the Vz phenomenon is recalibrated through the addition of a quantitative criterion based on the equivalent widths of the He I 4471, He II 4542, and He II 4686 spectral lines. The GOSSS O Vz and O V populations resulting from the newly adopted spectral classification criteria are comparatively analyzed. Read More

2016Apr
Affiliations: 1University of Alicante, University of Florida, 2University of Alicante

We study the area around the HII region Sh 2-234, including the young open cluster Stock 8, to investigate the extent and definition of the association Aur OB2 and the possible role of triggering in massive cluster formation. We obtained Str\"omgren and J,H,Ks photometry for Stock 8 and Str\"omgren photometry for two other cluster candidates in the area, which we confirm as young open clusters and name Alicante 11 and Alicante 12. We took spectroscopy of 33 early-type stars in the area, including the brightest cluster members. Read More

2016Mar
Affiliations: 1INFN Roma Tor Vergata, 2INFN Roma Tor Vergata, 3JINR Dubna, 4INFN LNGS, 5INFN LNGS, 6INFN LNGS, 7INR Kiev, 8INR Kiev, 9INFN Roma Tor Vergata, 10INFN Roma Tor Vergata, 11INFN Roma, 12INFN LNGS, 13INR Kiev, 14INR Kiev, 15INR Kiev, 16INR Kiev, 17ISM Kharkiv

A radiopure cadmium tungstate crystal scintillator, enriched in $^{106}$Cd to 66%, with mass of 216 g ($^{106}$CdWO$_4$), was used to search for double beta decay processes in $^{106}$Cd in coincidence with four ultra-low background high purity germanium detectors in a single cryostat. New improved limits on the double beta processes in $^{106}$Cd have been set on the level of $10^{20}- 10^{21}$ yr after 13085 h of data taking. In particular, the half-life limit on the two neutrino electron capture with positron emission, $T_{1/2}^{2\nu\varepsilon\beta^+}\geq 1. Read More

This is the third installment of GOSSS, a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R~2500 digital observations selected from the Galactic O-Star Catalog (GOSC). In this paper we present 142 additional stellar systems with O stars from both hemispheres, bringing the total of O-type systems published within the project to 590. Among the new objects there are 20 new O stars. Read More

A radiopure cadmium tungstate crystal scintillator, enriched in 106-Cd to 66%, with mass of 216 g (106-CdWO4) was used in coincidence with four ultra-low background HPGe detectors contained in a single cryostat to search for double beta decay processes in 106-Cd. New improved half-life limits on the double beta processes in 106-Cd have been set on the level of 1e20-1e21 yr after 13085 h of data taking deep underground (3600 m w.e. Read More

We consider a hybrid single-electron transistor (SET) constituted by a gate-controlled normal-metal island (N) connected to two voltage-biased superconducting leads (S) by means of two tunnel junctions (S-I-N-I-S), operated as a turnstile. We show that the exchange of photons between this system and the high-temperature electromagnetic environment where it is embedded enhances Andreev reflection, thereby limiting the single-electron tunneling accuracy. Read More

2015May
Affiliations: 1Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 2Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 3Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 4Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 5Univ. Roma Tor Vergata and INFN Roma Tor Vergata, 6Univ. Roma and INFN Roma, 7Univ. Roma and INFN Roma, 8INFN LNGS, 9INFN LNGS, 10INFN LNGS, 11IHEP Beijing, 12IHEP Beijing, 13IHEP Beijing, 14IHEP Beijing, 15IHEP Beijing, 16IHEP Beijing, 17IHEP Beijing

In the present paper the results obtained in the investigation of possible diurnal effects for low-energy single-hit scintillation events of DAMA/LIBRA-phase1 (1.04 ton $\times$ yr exposure) have been analysed in terms of an effect expected in case of Dark Matter (DM) candidates inducing nuclear recoils and having high cross-section with ordinary matter, which implies low DM local density in order to fulfill the DAMA/LIBRA DM annual modulation results. This effect is due to the different Earth depths crossed by those DM candidates during the sidereal day. Read More

Context: It appears that most (if not all) massive stars are born in multiple systems. At the same time, the most massive binaries are hard to find due to their low numbers throughout the Galaxy and the implied large distances and extinctions. AIMS: We want to study: [a] LS III +46 11, identified in this paper as a very massive binary; [b] another nearby massive system, LS III +46 12; and [c] the surrounding stellar cluster, Berkeley 90. Read More

Evidence of signatures associated with cryptographic modes of operation is established. Motivated by some analogies between cryptographic and dynamical systems, in particular with chaos theory, we propose an algorithm based on Lyapunov exponents of discrete dynamical systems to estimate the divergence among ciphertexts as the encryption algorithm is applied iteratively. The results allow to distinguish among six modes of operation, namely ECB, CBC, OFB, CFB, CTR and PCBC using DES, IDEA, TEA and XTEA block ciphers of 64 bits, as well as AES, RC6, Twofish, Seed, Serpent and Camellia block ciphers of 128 bits. Read More

2015Mar
Affiliations: 1Institute of Astronomy, University of Cambridge, 2DFISTS, Universidad de Alicante, 3DFISTS, Universidad de Alicante, 4DFISTS, Universidad de Alicante

In this study, we conduct a pilot program aimed at the red supergiant population of the Magellanic Clouds. We intend to extend the current known sample to the unexplored low end of the brightness distribution of these stars, building a more representative dataset with which to extrapolate their behaviour to other Galactic and extra-galactic environments. We select candidates using only near infrared photometry, and with medium resolution multi-object spectroscopy, we perform spectral classification and derive their line-of-sight velocities, confirming the nature of the candidates and their membership to the clouds. Read More

We consider the dynamics of a quantum phase-slip junction (QPSJ) -- a dual Josephson junction -- connected to a microwave source with frequency $\omega_\textrm{mw}$. With respect to an ordinary Josephson junction, a QPSJ can sustain dual Shapiro steps, consisting of well-defined current plateaus at multiple integers of $ e \omega_\textrm{mw} / \pi$ in the current-voltage (I-V) characteristic. The experimental observation of these plateaus has been elusive up to now. Read More

CAF\'E-BEANS is an on-going survey running on the 2.2 m telescope at Calar Alto. For more than two years, CAF\'E-BEANS has been collecting high-resolution spectra of early-type stars with the aim of detecting and characterising spectroscopic binaries. Read More

We provide a complete characterization of the astrophysical properties of the $\sigma$ Ori Aa,Ab,B hierarchical triple system, and an improved set of orbital parameters for the highly eccentric $\sigma$ Ori Aa,Ab spectroscopic binary. We compiled a spectroscopic dataset comprising 90 high-resolution spectra covering a total time span of 1963 days. We applied the Lehman-Filh\'es method for a detailed orbital analysis of the radial velocity curves and performed a combined quantitative spectroscopic analysis of the {$\sigma$ Ori Aa,Ab,B} system by means of the stellar atmosphere code FASTWIND. Read More

In this poster we present three developments related to the Galactic O-Star Spectroscopic Survey (GOSSS). First, we are making public the first version of MGB, an IDL code that allows the user to compare oberved spectra to a grid of spectroscopic standards to measure spectral types, luminosity classes, rotation indexes, and spectral qualifiers. Second, we present the associated grid of standard stars for the spectral types O2 to O9. Read More

2014Sep
Affiliations: 1Univ. Roma Tor Vergata, 2INFN Roma Tor Vergata, 3INFN LNGS, 4INFN LNGS, 5INFN LNGS, 6IHEP Beijing, 7Univ. Roma, 8Univ. Roma Tor Vergata, 9Univ. Roma Tor Vergata, 10IHEP Beijing, 11Univ. Roma, 12IHEP Beijing, 13IHEP Beijing, 14INFN Roma Tor Vergata, 15IHEP Beijing, 16IHEP Beijing, 17IHEP Beijing

This paper summarizes in a simple and intuitive way why the neutrons, the muons and the solar neutrinos cannot give any significant contribution to the DAMA annual modulation results. A number of these elements have already been presented in individual papers; they are recalled here. Afterwards, few simple considerations are summarized which already demonstrate the incorrectness of the claim reported in PRL 113 (2014) 081302. Read More

2014Jul
Affiliations: 1INFN Roma Tor Vergata, 2INFN Roma Tor Vergata, 3INFN Roma, 4INFN LNGS, 5INFN LNGS, 6INR Kiev, 7Univ. Tor Vergata, 8INFN Roma, 9INR Kiev, 10INFN Roma, 11INFN Roma

The radioactive contamination of a BaF$_2$ scintillation crystal with mass of 1.714 kg was measured over 101 hours in the low-background DAMA/R&D set-up deep underground (3600 m w.e. Read More

VISTA Variables in the V\'ia L\'actea (VVV) is one of six ESO Public Surveys using the 4 meter Visible and Infrared Survey Telescope for Astronomy (VISTA). The VVV survey covers the Milky Way bulge and an adjacent section of the disk, and one of the principal objectives is to search for new star clusters within previously unreachable obscured parts of the Galaxy. The primary motivation behind this work is to discover and analyze obscured star clusters in the direction of the inner Galactic disk and bulge. Read More

It has been suggested that the compact open cluster VdBH 222 is a young massive distant object. We set out to characterise VdBH 222 using a comprehensive set of multi-wavelength observations. We obtained multi-band optical (UBVR) and near-infrared (JHK) photometry of the cluster field, as well as multi-object and long-slit optical spectroscopy for a large sample of stars in the field. Read More

The design and operation of an electronic cooler based on a combination of superconducting tunnel junctions is described. The cascade extraction of hot-quasiparticles, which stems from the energy gaps of two different superconductors, allows for a normal metal to be cooled down to about 100 mK starting from a bath temperature of 0.5 K. Read More

Performance antipatterns document bad design patterns that have negative influence on system performance. In our previous work we formalized such antipatterns as logical predicates that predicate on four views: (i) the static view that captures the software elements (e.g. Read More

2014Mar
Affiliations: 1Univ. Roma Tor Vergata, 2INFN Roma Tor Vergata, 3Univ. Roma, 4INFN LNGS, 5INFN LNGS, 6INFN LNGS, 7IHEP Beijing, 8Univ. Roma, 9Univ. Roma Tor Vergata, 10Univ. Roma Tor Vergata, 11IHEP Beijing, 12INFN Roma, 13IHEP Beijing, 14IHEP Beijing, 15INFN Roma Tor Vergata, 16Univ. Roma, 17IHEP Beijing, 18IHEP Beijing, 19IHEP Beijing

The results obtained in the search for possible diurnal effect in the single-hit low energy data collected by DAMA/LIBRA-phase1 (total exposure: 1.04 ton x yr) deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N. Read More

Context: Young massive clusters are key to map the Milky Way's structure, and near-IR large area sky surveys have contributed strongly to the discovery of new obscured massive stellar clusters. Aims: We present the third article in a series of papers focused on young and massive clusters discovered in the VVV survey. This article is dedicated to the physical characterization of VVV CL086, using part of its OB-stellar population. Read More

The DAMA/LIBRA experiment is composed by about 250 kg of highly radiopure NaI(Tl). It is in operation at the underground Gran Sasso National Laboratory of the INFN. The main aim of the experiment is to investigate the Dark Matter (DM) particles in the Galactic halo by exploiting the model independent DM annual modulation signature. Read More

Barium fluoride (BaF$_2$) crystal scintillators are promising detectors to search for double beta decay processes in $^{130}$Ba ($Q_{2{\beta}}$ = 2619(3) keV) and $^{132}$Ba ($Q_{2{\beta}}$ = 844(1) keV). The $^{130}$Ba isotope is of particular interest because of the indications on 2${\beta}$ decay found in two geochemical experiments. The radioactive contamination of BaF$_2$ scintillation crystal with mass of 1. Read More

Most animals have separate sexes. The differential expression of gene products, in particular that of gene regulators, is underlying sexual dimorphism. Analyses of sex-biased expression have focused mostly in protein coding genes. Read More

2013Aug
Affiliations: 1Univ. Roma Tor Vergata, 2INFN Roma Tor Vergata, 3Univ. Roma, 4INFN LNGS, 5INFN LNGS, 6INFN LNGS, 7IHEP Beijing, 8Univ. Roma, 9Univ. Roma Tor Vergata, 10Univ. Roma Tor Vergata, 11IHEP Beijing, 12INFN Roma, 13IHEP Beijing, 14IHEP Beijing, 15INFN Roma Tor Vergata, 16Univ. Roma, 17IHEP Beijing, 18IHEP Beijing, 19IHEP Beijing

The results obtained with the total exposure of 1.04 ton x yr collected by DAMA/LIBRA-phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N. Read More

Results on the search for rare nuclear decays with the ultra low background facility STELLA at the LNGS using gamma ray spectrometry are presented. In particular, the best T1/2 limits were obtained for double beta processes in 96Ru and 104Ru. Several isotopes, which potentially decay through different double beta decay channels, including also possible resonant double electron captures, were investigated for the first time (156Dy, 158Dy, 184Os, 192Os, 190Pt, 198Pt). Read More

We consider a voltage-biased Normal metal-Insulator-Superconductor (NIS) tunnel junction, connected to a high-temperature external electromagnetic environment. This model system features the commonly observed subgap leakage current in NIS junctions through photon-assisted tunneling which is detrimental for applications. We first consider a NIS junction directly coupled to the environment and analyze the subgap leakage current both analytically and numerically; we discuss the link with the phenomenological Dynes parameter. Read More

2013Jun
Affiliations: 1Univ. and INFN Roma Tor Vergata, 2Univ. and INFN Roma Tor Vergata, 3Univ. and INFN Roma Tor Vergata, 4Univ. and INFN Roma Tor Vergata, 5Univ. and INFN Roma Tor Vergata, 6Univ. and INFN Roma, 7Univ. and INFN Roma, 8Univ. and INFN Roma, 9INFN LNGS, 10INFN LNGS, 11INFN LNGS, 12IHEP Beijing, 13IHEP Beijing, 14IHEP Beijing, 15IHEP Beijing, 16IHEP Beijing, 17IHEP Beijing

Experimental observations and theoretical arguments at Galaxy and larger scales have suggested that a large fraction of the Universe is composed by Dark Matter particles. This has motivated the DAMA experimental efforts to investigate the presence of such particles in the galactic halo by exploiting a model independent signature and very highly radiopure set-ups deep underground. Few introductory arguments are summarized before presenting a review of the present model independent positive results obtained by the DAMA/NaI and DAMA/LIBRA set-ups at the Gran Sasso National Laboratory of the INFN. Read More

2013May
Affiliations: 1INFN Roma Tor Vergata, 2INFN Roma Tor Vergata, 3INFN Roma, 4INFN LNGS, 5INFN LNGS, 6INFN LNGS, 7IHEP Beijing, 8INFN Roma, 9INFN Roma Tor Vergata, 10IHEP Beijing, 11INFN Roma, 12INFN LNGS, 13IHEP Beijing, 14INFN Roma Tor Vergata, 15IHEP Beijing, 16INR Kiev, 17IHEP Beijing, 18IHEP Beijing

A new search for production of correlated e+e- pairs in the alpha decay of 241Am has been carried out deep underground at the Gran Sasso National Laboratory of the I.N.F. Read More

Genetic linkage may result in the expression of multiple products from a polycistronic transcript, under the control of a single promoter. In animals, protein-coding polycistronic transcripts are rare. However, microRNAs are frequently clustered in the genomes of animals, and these clusters are often transcribed as a single unit. Read More

2013Mar
Affiliations: 1Universidad de Alicante, 2Universidad de Alicante, 3Universidad de Alicante, 4Universidad de Alicante, 5Open University

The open cluster Stephenson 2 contains the largest collection of red supergiants known in the Galaxy, and at present is the second most massive young cluster known in the Milky Way. We have obtained multi-epoch, intermediate-resolution spectra around the CaII triplet for more than 30 red supergiants in Stephenson~2 and its surroundings. We find a clear separation between a majority of RSGs having spectral types M0-M2 and the brightest members in the NIR, which have very late spectral types and show strong evidence for heavy mass loss. Read More

The open cluster NGC 7419 is known to contain five red supergiants and a very high number of Be stars. However, there are conflicting reports about its age and distance that prevent a useful comparison with other clusters. We intend to obtain more accurate parameters for NGC 7419, using techniques different from those of previous authors, so that it may be used as a calibrator for more obscured clusters. Read More

2013Jan
Affiliations: 1Univ. and INFN Roma Tor Vergata, 2Univ. and INFN Roma Tor Vergata, 3Univ. and INFN Roma Tor Vergata, 4Univ. and INFN Roma, 5Univ. and INFN Roma, 6Univ. and INFN Roma, 7INFN LNGS, 8INFN LNGS, 9IHEP Beijing, 10IHEP Beijing, 11IHEP Beijing, 12IHEP Beijing, 13IHEP Beijing, 14Univ. and INFN Roma Tor Vergata, 15IHEP Beijing

The DAMA/LIBRA experiment, running at the Gran Sasso National Laboratory of the I.N.F. Read More

2013Jan
Affiliations: 1INFN Roma Tor Vergata, 2INFN Roma Tor Vergata, 3INFN Roma, 4INFN LNGS, 5INR Kiev, 6INFN Roma Tor Vergata, 7INFN Roma Tor Vergata, 8INFN Roma, 9NSC Kharkiv, 10NSC Kharkiv, 11INFN LNGS, 12INR Kiev, 13INFN Roma, 14NSC Kharkiv, 15INR Kiev

A search for double-beta decay of osmium has been realized for the first time with the help of an ultra-low background HPGe gamma detector at the underground Gran Sasso National Laboratories of the INFN (Italy). After 2741 h of data taking with a 173 g ultra-pure osmium sample limits on double-beta processes in 184Os have been established at the level of T_{1/2} about 10^{14}-10^{17} yr. Possible resonant double-electron captures in 184Os were searched for with a sensitivity T_{1/2} about 10^{16} yr. Read More

2012Nov
Affiliations: 1Univ. and INFN Roma Tor Vergata, 2Univ. and INFN Roma Tor Vergata, 3Univ. and INFN Roma, 4INFN LNGS, 5INFN LNGS, 6IHEP Beijing, 7Univ. and INFN Roma, 8Univ. and INFN Roma Tor Vergata, 9IHEP Beijing, 10Univ. and INFN Roma, 11IHEP Beijing, 12Univ. and INFN Roma Tor Vergata, 13IHEP Beijing, 14IHEP Beijing, 15IHEP Beijing

A few final comments on arXiv:1210.7548 are given to confute incorrect arguments claimed there. Read More

2012Oct
Affiliations: 1Univ. and INFN Roma Tor Vergata, 2Univ. and INFN Roma Tor Vergata, 3Univ. and INFN Roma, 4INFN LNGS, 5INFN LNGS, 6IHEP Beijing, 7Univ. and INFN Roma, 8Univ. and INFN Roma Tor Vergata, 9IHEP Beijing, 10Univ. and INFN Roma, 11IHEP Beijing, 12Univ. and INFN Roma Tor Vergata, 13IHEP Beijing, 14IHEP Beijing, 15IHEP Beijing

We briefly remind references and arguments, already discussed in the past, which confute erroneous claims in arXiv:1210.5501. Read More

2012Oct
Affiliations: 1University of Alicante, Spain, 2University of Alicante, Spain

The discovery of several clusters of red supergiants towards l=24-30 deg has triggered interest in this area of the Galactic plane, where lines of sight are very complex and previous explorations of the stellar content were very preliminary. We attempt to characterise the stellar population associated with the HII region RCW173 (Sh2-60), located at l=25.3 deg, as previous studies have suggested that this population could be beyond the Sagittarius arm. Read More

2012Aug
Affiliations: 1Alicante, 2Alicante, 3Alicante, 4Spanish VO, CAB-CSIC, 5Open University, 6IAC, 7Spanish VO, CAB-CSIC

Several clusters of red supergiants have been discovered in a small region of the Milky Way close to the base of the Scutum-Crux Arm and the tip of the Long Bar. Population synthesis models indicate that they must be very massive to harbour so many supergiants. Among them, Stephenson 2, with a core grouping of 26 RSGs, is a strong candidate to be the most massive cluster in the Galaxy. Read More