741 research outputs found
Absolute Calibration of the Auger Fluorescence Detectors
Absolute calibration of the Pierre Auger Observatory fluorescence detectors
uses a light source at the telescope aperture. The technique accounts for the
ombined effects of all detector components in a single measurement. The
calibrated 2.5 m diameter light source fills the aperture, providing uniform
illumination to each pixel. The known flux from the light source and the
response of the acquisition system give the required calibration for each
pixel. In the lab, light source uniformity is studied using CCD images and the
intensity is measured relative to NIST-calibrated photodiodes. Overall
uncertainties are presently 12%, and are dominated by systematics.Comment: 4 pages, 3 figure. Submitted to the 29th ICRC, Pune, Indi
Multi-wavelength Calibration Procedure for the Pierre Auger Observatory Fluorescence Detectors
We present a method to measure the relative spectral response of the Pierre
Auger Observatory Fluorescence Detector. The calibration was done at
wavelengths of 320, 337, 355, 380 and 405 nm using an end-to-end technique in
which the response of all detector components are combined in a single
measurement. A xenon flasher and notch-filters were used as the light source
for the calibration device. The overall uncertainty is 5%.Comment: Submitted to Astroparticle Physics. V2: section 5.2 extended; author
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Response to Letter to the Editor: "Alemtuzumab-Induced Thyroid Dysfunction Exhibits Distinctive Clinical and Immunological Features".
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Scientific Meetings Database: A New Tool for CTBT-Related International Cooperation
The mission of international cooperation is defined in the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Ways and means of implementation were the subject of discussion during the International Cooperation Workshop held in Vienna in November 1998, and during the Regional Workshop for CTBTO International Cooperation held in Cairo, Egypt in June 1999. In particular, a database of ''Scientific and Technical Meetings Directly or Indirectly Related to CTBT Verification-Related Technologies'' was developed by the CTBTO PrepCom/PTS/International Cooperation section and integrated into the organization's various web sites in cooperation with the U.S. Department of Energy CTBT Research and Development Program. This database, the structure and use of which is described in this paper/presentation is meant to assist the CTBT-related scientific community in identifying worldwide expertise in the CTBT verification-related technologies and should help experts, particularly those of less technologically advanced States Signatories, to strengthen contacts and to pursue international cooperation under the Tredy regime. Specific opportunities for international cooperation, in particular those provided by active participation in the use and further development of this database, are presented in this paper and/or presentation
Crescimento inicial de Mimosa scabrella Benth., Schinus terebinthifolius Raddi e Allophylus edulis (St. Hill) Radl. sob diferentes regimes de adubação.
O presente trabalho estudou a produção de mudas em viveiro envolvendo as espécies Mimosa scabrella Benth. (bracatinga), Schinus terebinthifolius Raddi (aroeira-vermelha) e Allophylus edulis (ST Hil.) Radl (vacum). O experimento foi conduzido no Município de Colombo, PR, no viveiro da Embrapa Florestas. Em fevereiro de 2004, foi realizada a semeadura das três espécies, em tubetes com cerca de 50 cm3, preenchidos com 70% de substrato comercial a base de casca de pínus e vermiculita e 30% de fibra de coco granulada. Os tratamentos corresponderam à três diferentes dosagens de adubos, parceladas em adubação de base e de cobertura, dispostos em blocos ao acaso, com parcelas de nove mudas e sete repetições, correspondendo a 63 mudas por espécie/tratamento. Aos quatro meses após a semeadura, foi realizada a avaliação do experimento, com medições de altura e diâmetro do caule de todas as mudas, e selecionada uma muda por repetição para as análises destrutivas de biomassa seca (parte aérea e radicial), tendo como critério a escolha da muda mais próxima da média da repetição. A aroeira-vermelha foi a espécie que melhor respondeu à adubação, seguida da bracatinga. Diferentemente das demais espécies, o vacum apresentou baixa exigência quanto à adubação no processo de produção de mudas. O crescimento das espécies pode ter sido mais lento devido à época do ano, que envolveu o inverno
The new carbon symbiotic star IPHAS J205836.43+503307.2
We are performing a search for symbiotic stars using IPHAS, the INT Halpha
survey of the northern Galactic plane, and follow-up observations. Candidate
symbiotic stars are selected on the basis of their IPHAS and near-IR colours,
and spectroscopy and photometry are obtained to determine their nature. We
present here observations of the symbiotic star candidate IPHAS
J205836.43+503307.2. The optical spectrum shows the combination of a number of
emission lines, among which are the high-excitation species of [OIII], HeII,
[Ca V], and [Fe VII], and a red continuum with the features of a star at the
cool end of the carbon star sequence. The nebular component is spatially
resolved: the analysis of the spatial profile of the [NII]6583 line in the
spectrum indicates a linear size of ~2.5 arcsec along the east-west direction.
Its velocity structure suggests an aspherical morphology. The near-infrared
excess of the source, which was especially strong in 1999, indicated that a
thick circumstellar dust shell was also present in the system. The carbon star
has brightened in the last decade by two to four magnitudes at red and
near-infrared wavelengths. Photometric monitoring during a period of 60 days
from November 2010 to January 2011 reveals a slow luminosity decrease of 0.2
magnitudes. From the observed spectrophotometric properties and variability, we
conclude that the source is a new Galactic symbiotic star of the D-type, of the
rare kind that contains a carbon star, likely a carbon Mira. Only two other
systems of this type are known in the Galaxy.Comment: 6 pages, 4 figure
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