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Discovery of the Bright Trans-Neptunian Object 2000 EB173  [PDF]
Ignacio Ferrin,D. Rabinowitz,B. Schaefer,J. Snyder,N. Ellman,B. Vicente,A. Rengstorf,D. Depoy,S. Salim,P. Andrews,C. Bailyn,C. Baltay,C. Briceno,P. Coppi,M. Deng,W. Emmet,A. Oemler,C. Sabbey,J. Shin,S. Sofia,W. van Altena,K. Vivas,C. Abad,A. Bongiovanni,G. Bruzual,F. Della Prugna,D. Herrera,G. Magris,J. Mateu,R. Pacheco,Ge. Sanchez,Gu. Sanchez,H. Schenner,J. Stock,K. Vieira,F. Fuenmayor,J. Hernandez,O. Naranjo,P. Rosenzweig,C. Secco,G. Spavieri,M. Gebhard,H. Honeycutt,S. Mufson,J. Musser,S. Pravdo,E. Helin,K. Lawrence
Physics , 2000, DOI: 10.1086/319109
Abstract: We describe the discovery circumstances and photometric properties of 2000 EB173, now one of the brightest trans-Neptunian objects (TNOs) with opposition magnitude m_R=18.9 and also one of the largest Plutinos, found with the drift-scanning camera of the QUEST Collaboration, attached to the 1-m Schmidt telescope of the National Observatory of Venezuela. We measure B-V = 0.99 +/- 0.14 and V-R = 0.57 +/- 0.05, a red color observed for many fainter TNOs. At our magnitude limit m_R = 20.1 +/- 0.20, our single detection reveals a sky density of 0.015 (+0.034, -0.012) TNOs per deg^2 (the error bars are 68% confidence limits), consistent with fainter surveys showing a cumulative number proportional to 10^0.5m_R. Assuming an inclination distribution of TNOs with FWHM exceeding 30 deg, it is likely that one hundred to several hundred objects brighter than m_R=20.1 remain to be discovered.
On-Sky Tests of an A/R Coated Silicon Grism on board NICS@TNG  [PDF]
Fabrizio Vitali,Vittorio Foglietti,Dario Lorenzetti,Elena Cianci,Francesca Ghinassi,Avet Harutyunyan,Simone Antoniucci,Carlos Riverol,Luis Riverol
Physics , 2014, DOI: 10.1117/12.2054916
Abstract: We present the results of our project for the design and construction and on-sky test of silicon grisms. The fabrication of such devices is a complex and critical process involving litho-masking, anisotropic etching and direct bonding techniques. After the successful fabrication of the silicon grating, we have optimized the bonding of the grating onto the hypotenuse of a silicon prism to get the final prototype. After some critical phases during the experimentation a silicon grism with 363 grooves/mm and a blaze angle of 14 degrees has been eventually fabricated. The application of an A/R coating on both the surfaces has been the last step: this procedure is critical because of the groove geometry of the diffraction grating, whose performace might be compromised by the coating. Then, the grism was inserted in the filter wheel of the Near Infrared camera NICS, at the focal plane of the National Galileo Telescope (TNG), the 3.5 m Italian facility in the Canary Islands (E). The result of the on-sky tests are given in detail.
NICS-TNG infrared spectroscopy of NGC1068: the first extragalactic measurement of [PII] and a new tool to constrain the origin of [FeII] line emission in galaxies  [PDF]
E. Oliva,A. Marconi,R. Maiolino,L. Testi,F. Mannucci,F. Ghinassi,J. Licandro,L. Origlia,C. Baffa,A. Checcucci,G. Comoretto,V. Gavryussev,S. Gennari,E. Giani,L. K. Hunt,F. Lisi,D. Lorenzetti,G. Marcucci,L. Miglietta,M. Sozzi,P. Stefanini,F. Vitali
Physics , 2001, DOI: 10.1051/0004-6361:20010214
Abstract: We report 0.9-1.4 micron spectroscopic observations of NGC1068 collected during the commissioning phase of the near infrared camera spectrometer (NICS) of the Telescopio Nazionale Galileo (TNG). These yielded the first extragalactic measurement of [PII] (1.188 micron) line emission. In the central 0.75"x2" the [FeII]/[PII] line-intensity ratio is close to unity, similar to that measured in the Orion bar and a factor of about 20 smaller than in supernova remnants. This indicates that most of iron is locked into grains and, therefore, argues against shock excitation being the primary origin of [FeII] line emission in the central regions of NGC1068. We propose the [FeII]/[PII] ratio as a simple and effective tool to study and perhaps resolve the long debated questions related to the origin of [FeII] line emission and, more generally, to constrain the role of shock excitation in active galaxies.
NICS-TNG low-resolution 0.85-2.45um spectra of L-Dwarfs: a near-infrared spectral classification scheme for faint dwarfs  [PDF]
L. Testi,F. D'Antona,F. Ghinassi,J. Licandro,A. Magazzu',R. Maiolino,F. Mannucci,A. Marconi,N. Nagar,A. Natta,E. Oliva
Physics , 2001, DOI: 10.1086/320348
Abstract: We present complete near-infrared (0.85-2.45 um), low-resolution (~100) spectra of a sample of 26 disk L-dwarfs with reliable optical spectral type classification. The observations have been obtained with NICS at the TNG using a prism-based optical element (the Amici device) that provides a complete spectrum of the source on the detector. Our observations show that low-resolution near-infrared spectroscopy can be used to determine the spectral classification of L-dwarfs in a fast but accurate way. We present a library of spectra that can be used as templates for spectral classification of faint dwarfs. We also discuss a set of near-infrared spectral indices well correlated with the optical spectral types that can be used to accurately classify L-dwarfs earlier than L6.
Photometric Light Curve for the Kuiper Belt Object 2000 EB173 on 78 Nights  [PDF]
Bradley E. Schaefer,David L. Rabinowitz
Physics , 2002, DOI: 10.1006/icar.2002.6958
Abstract: Kuiper Belt Objects (KBOs) are generally very faint and cannot in practice be monitored with a well-sampled long-term light curve; so our discovery of the bright KBO 2000 EB173 offers an excellent opportunity for synoptic studies. We present a well-sampled photometric time series (77 R magnitudes and 29 V magnitudes on 78 nights) over a 225-day time span centered on the 2001 opposition. The light curve (corrected to the year 2001 opposition distance) varies from 19.11 to 19.39 mag with a single peak that is smooth, time symmetric, and coincident with opposition. All variations in the light curve are consistent with a linear opposition surge (Ropp = 19.083 + 0.125Xalpha, where alpha is the solar phase angle), while any rotational modulation must have a peak-to-peak amplitude of less than 0.097 mag. This is the first measured opposition surge for any KBO (other than Pluto). The V-R color is 0.63+-0.02, with no apparent variation with phase at the few percent level. With R=19.11 at opposition, 2000 EB173 remains the brightest known KBO and a prime target for future photometric and spectroscopic studies.
The TNG Near Infrared Camera Spectrometer  [PDF]
C. Baffa,G. Comoretto,S. Gennari,F. Lisi,E. Oliva,V. Biliotti,A. Checcucci,V. Gavrioussev,E. Giani,F. Ghinassi,L. K. Hunt,R. Maiolino,F. Mannuci,G. Marcucci,M. Sozzi,P. Stefanini,L. Testi
Physics , 2001, DOI: 10.1051/0004-6361:20011194
Abstract: NICS (acronym for Near Infrared Camera Spectrometer) is the near-infrared cooled camera-spectrometer that has been developed by the Arcetri Infrared Group at the Arcetri Astrophysical Observatory, in collaboration with the CAISMI-CNR for the TNG (the Italian National Telescope Galileo at La Palma, Canary Islands, Spain). As NICS is in its scientific commissioning phase, we report its observing capabilities in the near-infrared bands at the TNG, along with the measured performance and the limiting magnitudes. We also describe some technical details of the project, such as cryogenics, mechanics, and the system which executes data acquisition and control, along with the related software.
Infrared spectroscopy of the largest known trans-neptunian object 2001 KX76  [PDF]
J. Licandro,F. Ghinassi,L. Testi
Physics , 2002, DOI: 10.1051/0004-6361:20020533
Abstract: We report complete near-infrared (0.9-2.4 $\mu$m) spectral observations of the largest know trans-neptunian objects (TNO) 28976 = 2001 KX$_{76}$ taken in two different nights using the new Near Infrared Camera Spectrometer (NICS) attached to the 3.56m Telescopio Nazionale Galileo (TNG). The spectra are featureless and correspond to a neutral colored object. Our observations indicate that the surface of 2001 KX$_{76}$ is probably highly evolved due to long term irradiation, and that collisional resurfacing processes have not played an important role in its evolution.
Tentative insight into the multiplicity of the persistent dust maker WR106 from X-ray observations  [PDF]
M. De Becker
Physics , 2015, DOI: 10.1016/j.newast.2015.05.002
Abstract: This paper presents the results of the analysis of the very first dedicated X-ray observation with XMM-Newton of WR106. This carbon-rich WC9d Wolf-Rayet star belongs to the category of persistent dust makers (WCd stars). The issue of the multiplicity of these dust makers is pivotal to understand the dust formation process, and in this context X-ray observations may allow to reveal an X-ray emission attributable to colliding-winds in a binary system. The main result of this analysis is the lack of detection of X-rays coming from WR106. Upper limits on the X-ray flux are estimated, but the derived numbers are not sufficient to provide compelling constraints on the existence or not of a colliding-wind region. Detailed inspection of archive data bases reveals that persistent dust makers have been poorly investigated by the most sensitive X-ray observatories. Certainly, the combination of several approaches to indirectly constrain their multiplicity should be applied to lift a part of the veil on the nature of these persistent dust makers.
Passive Classification of Wireless NICs during Rate Switching  [cached]
Cherita L. Corbett,Raheem A. Beyah,John A. Copeland
EURASIP Journal on Wireless Communications and Networking , 2008, DOI: 10.1155/2008/495070
Abstract: Computer networks have become increasingly ubiquitous. However, with the increase in networked applications, there has also been an increase in difficulty to manage and secure these networks. The proliferation of 802.11 wireless networks has heightened this problem by extending networks beyond physical boundaries. We propose the use of spectral analysis to identify the type of wireless network interface card (NIC). This mechanism can be applied to support the detection of unauthorized systems that use NICs which are different from that of a legitimate system. We focus on rate switching, a vaguely specified mechanism required by the 802.11 standard that is implemented in the hardware and software of the wireless NIC. We show that the implementation of this function influences the transmission patterns of a wireless stream, which are observable through traffic analysis. Our mechanism for NIC identification uses signal processing to analyze the periodicity embedded in the wireless traffic caused by rate switching. A stable spectral profile is created from the periodic components of the traffic and used for the identity of the wireless NIC. We show that we can distinguish between NICs manufactured by different vendors and NICs manufactured by the same vendor using their spectral profiles.
Passive Classification of Wireless NICs during Rate Switching  [cached]
Corbett CheritaL,Beyah RaheemA,Copeland JohnA
EURASIP Journal on Wireless Communications and Networking , 2008,
Abstract: Computer networks have become increasingly ubiquitous. However, with the increase in networked applications, there has also been an increase in difficulty to manage and secure these networks. The proliferation of 802.11 wireless networks has heightened this problem by extending networks beyond physical boundaries. We propose the use of spectral analysis to identify the type of wireless network interface card (NIC). This mechanism can be applied to support the detection of unauthorized systems that use NICs which are different from that of a legitimate system. We focus on rate switching, a vaguely specified mechanism required by the 802.11 standard that is implemented in the hardware and software of the wireless NIC. We show that the implementation of this function influences the transmission patterns of a wireless stream, which are observable through traffic analysis. Our mechanism for NIC identification uses signal processing to analyze the periodicity embedded in the wireless traffic caused by rate switching. A stable spectral profile is created from the periodic components of the traffic and used for the identity of the wireless NIC. We show that we can distinguish between NICs manufactured by different vendors and NICs manufactured by the same vendor using their spectral profiles.
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