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This paper gives the 2006 self-consistent set of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2006 adjustment takes into account the data considered in the 2002 adjustment as well as the data that became available between 31 December 2002, the closing date of that adjustment, and 31 December 2006, the closing date of the new adjustment. The new data have led to a significant reduction in the uncertainties of many recommended values. The 2006 set replaces the previously recommended 2002 CODATA set and also may be found on the World Wide Web at physics.nist.gov/constants.
We report first results of a multifrequency campaign from radio to hard X-ray energies of the prominent gamma-ray blazar 3C 279, which was organised around an INTEGRAL ToO observation in January 2006, and triggered on its optical state. The variable blazar was observed at an intermediate optical state, and a well-covered multifrequency spectrum from radio to hard X-ray energies could be derived. The SED shows the typical two-hump shape, the signature of non-thermal synchrotron and inverse-Compton (IC) emission from a relativistic jet. By the significant exposure times of INTEGRAL and Chandra, the IC spectrum (0.3 - 100 keV) was most accurately measured, showing - for the first time - a possible bending. A comparison of this 2006 SED to the one observed in 2003, also centered on an INTEGRAL observation, during an optical low-state, reveals the surprising fact that - despite a significant change at the high-energy synchrotron emission (near-IR/optical/UV) - the rest of the SED remains unchanged. In particular, the low-energy IC emission (X- and hard X-ray energies) remains the same as in 2003, proving that the two emission components do not vary simultaneously, and provides strong co
Recent measurements of the cosmic microwave background radiation (CMB), particularly when combined with other datasets, have revolutionised our knowledge of the values of the basic cosmological parameters. Here we summarize the state of play at the end of 2006, focusing on the combination of CMB measurements with the power spectrum of galaxy clustering. We compare the constraints derived from the extant CMB data circa 2005 and the final 2dFGRS galaxy power spectrum, with the results obtained when the WMAP 1-year data is replaced by the 3-year measurements (hereafter WMAP1 and WMAP3). Remarkably, the picture has changed relatively little with the arrival of WMAP3, though some aspects have been brought into much sharper focus. One notable example of this is the index of primordial scalar fluctuations, n_s. Prior to WMAP3, Sanchez et al. (2006) found that the scale invariant value of n_s = 1 was excluded at the 95% level. With WMAP3, this becomes a 3sigma result, with implications for models of inflation. We find some disagreement between the constraints on certain parameters when the 2dFGRS P(k) is replaced by the SDSS measurement. This suggests that more work is needed to understand
We present infrared spectroscopy of the recurrent nova RS Ophiuchi, obtained 11.81, 20.75 and 55.71 days following its 2006 eruption. The spectra are dominated by hydrogen recombination lines, together with HeI, OI and OII lines; the electron temperature of ~10^4 K implied by the recombination spectrum suggests that we are seeing primarily the wind of the red giant, ionized by the ultraviolet flash when RS Oph erupted. However, strong coronal emission lines (i.e. emission from fine structure transitions in ions having high ionization potential) are present in the last spectrum. These imply a temperature of 930000K for the coronal gas; this is in line with x-ray observations of the 2006 eruption. The emission line widths decrease with time in a way that is consistent with the shock model for the x-ray emission.
As mentioned in the preceding additional information (hereafter called Part I), a series of strong earthquakes with magnitudes between 5.2 and 5.9-units occurred during the two weeks period: 3 to 19 April, 2006 with epicenters lying at distances 80 to 100 km west of PAT station. Here, we show that the analysis in the natural time of the seismicity that occurred after the Seismic Electric Signals (SES) activity on February 13, 2006, specifies the occurrence time of the initiation of the aforementioned earthquake activity within a narrow range around two days. Furthermore, we provide the most recent information on some points mentioned in the main text.
RS Ophiuchi began its latest outburst on 2006 February 12. Previous outbursts have indicated that high velocity ejecta interact with a pre-existing red giant wind, setting up shock systems analogous to those seen in Supernova Remnants. However, in the previous outburst in 1985, X-ray observations did not commence until 55 days after the initial explosion. Here we report on Swift observations covering the first month of the 2006 outburst with the Burst Alert (BAT) and X-ray Telescope (XRT) instruments. RS Oph was clearly detected in the BAT 14-25 keV band from t=0 to $t\sim6$ days. XRT observationsfrom 0.3-10 keV, started at 3.17 days after outburst. The rapidly evolving XRT spectra clearly show the presence of both line and continuum emission which can be fitted by thermal emission from hot gas whose characteristic temperature, overlying absorbing column, $[N_H]_W$, and resulting unabsorbed total flux decline monotonically after the first few days. Derived shock velocities are in good agreement with those found from observations at other wavelengths. Similarly, $[N_H]_W$ is in accord with that expected from the red giant wind ahead of the forward shock. We confirm the basic models
The detection of very high energy neutrinos of galactic/extragalactic origin requires very large detectors and a large overburden as a shield against the background of cosmic ray muons. ANTARES is at present the largest (effective area ~0.05 km2) experiment currently under construction in the northern hemisphere. It is being built and installed at a depth of 2500m in the Mediterranean sea, near the Southern French coast, by a large European collaboration. A three-dimensional array of photomultipliers are used to detect the Cherenkov light emitted by neutrino-induced muons. The array, when completed, will consists of 12 lines each covering a vertical length of about 480 m and equipped with 75 photomultipliers arranged in triplets. The readout electronics is connected to an on-shore laboratory through a 42 km long electro-optical cable. The final detector design has been completed. An instrumented line (called MILOM) has been installed in the spring of 2005; the first string (Line 1) is in acquisition starting from February 2006, and the second (Line 2) from September 2006. The physics motivations of the experiment, the details of the construction and installation, together with prel
In this paper we present the results of the past two years' observations on the galactic microquasar LS I +61 303 with the Whipple 10m gamma-ray telescope. The recent MAGIC detection of the source between 200 GeV and 4 TeV suggests that the source is periodic with very high energy (VHE) gamma-ray emission linked to its orbital cycle. The entire 50-hour data set obtained with Whipple from 2004 to 2006 was analyzed with no reliable detection resulting. The upper limits obtained in the 2005-2006 season covered several of the same epochs as the MAGIC Telescope detections, albeit with lower sensitivity. Upper limits are placed on emission during the orbital phases of 0->0.1 and 0.8->1, phases which are not included in the MAGIC data set.
RS Ophiuchi is one of the well-observed recurrent novae and also a candidate progenitor of Type Ia supernovae. Its sixth recorded outburst was discovered on 12 February 2006. Detection of a supersoft X-ray phase will provide a firm confirmation of hydrogen shell-burning on the white dwarf and its turn-on/turn-off dates strongly constrain a mass range of the white dwarf, which clarify whether or not RS Oph becomes a Type Ia supernova. For a timely detection of its supersoft X-ray phase, we have calculated outburst evolution of RS Oph based on the optically thick wind theory and predicted a supersoft X-ray phase for the 2006 outburst: it will most probably start on day 80-90 and continue until day 110-120 after the optical maximum. Its duration is so short as only a month or so. We strongly recommend multiple observations during April, May, and June of 2006 to detect turn-on and turn-off times of the supersoft X-ray phase.
A concise look at the big picture of particle physics, including the status of the Standard Model, neutrinos, supersymmetry, extra dimensions and cosmology. Based upon the theoretical summary presented at the XLIst Rencontres de Moriond on Electroweak Interactions and Unified Theories, La Thuile, 11-18 March 2006.
The origin of the asymmetry between matter and anti-matter of the Universe has been one of the great challenges in particle physics and cosmology. Leptogenesis as a mechanism for generating the cosmological baryon asymmetry of the Universe has gained significant interests ever since the advent of the evidence of non-zero neutrino masses. In these lectures presented at TASI 2006, I review various realizations of leptogenesis and allude to recent developments in this subject.
This paper presents a summary of the theoretical presentations to the international workshop "Diffraction 2006". The range of topics covered during the workshop was quite broad and this summary is therefore somewhat selective covering recent developments in BFKL physics, exclusive processes, saturation dynamics, DIS and structure functions and coherence in QCD.
We present results of our modeling the H-alpha line profile along the 2006 RS Oph outburst. At day 1.38 the very broad component of the H-alpha profile was possible to fit by a bipolar wind model. The model corresponds to a very fast acceleration of the wind particles, and the line luminosity of about 2900 (d/1.6 kpc)^2 solar luminosities to the mass-loss rate of around (1-2) x 10E-4 solar masses per year. During days 10-30 the broad component shrank to FWZI = 1800 km/s. It could be associated with expanding ring and its satellite components at about +/- 2430 km/s with bipolar jets. Later observations made at day 57 and 209 indicated a decrease in both the mass-loss rate (1xE-5 - 1xE-6 solar masses per year) and the wind acceleration. During the quiet phase, emission bumps observed sporadically in the line wings could reflect clumpy ejections by the central star.
On the occasion of the 125-th anniversary of Newcomb's paper, a bibliography of academic work related to Benford's law from its year of origin 1881 to 2006 has been compiled.
We present a preliminary report on the broadband optical photometry of the 2006 outburst of the recurrent nova RS Ophiuchi. These data were obtained using the robotic 2m Liverpool Telescope and cover the outburst from day 27 through day 548.
An overview of new experimental results on high-\pT{} particle production and jets in heavy ion collisions from the Quark Matter 2006 conference is presented.
Near-infrared spectra are presented for the recent 2006 outburst of the recurrent nova RS Ophiuchi (RS Oph).We report the rare detection of an infrared shock wave as the nova ejecta plows into the pre-existing wind of the secondary in the RS Oph system consisting of a white dwarf (WD) primary and a red giant secondary. The evolution of the shock is traced through a free expansion stage to a decelerative phase. The behavior of the shock velocity with time is found to be broadly consistent with current shock models. The present observations also imply that the WD in the RS Oph system has a high mass indicating that it could be a potential SNIa candidate. We also discuss the results from a recent study showing that the near-IR continuum from the recent RS Oph eruption does not originate in an expanding fireball. However, the present work shows that the IR line emission does have an origin in an expanding shock wave.
The status of $B$ physics, CP violation and related measurements at the time of the Beauty 2006 conference are summarized. Particular attention is given to the exciting prospects that lie ahead, at the commencement of the LHC era, and beyond.
Commission 10 deals with solar activity in all of its forms, ranging from the smallest nanoflares to the largest coronal mass ejections. This report reviews scientific progress over the roughly two-year period ending in the middle of 2008. This has been an exciting time in solar physics, highlighted by the launches of the Hinode and STEREO missions late in 2006. The report is reasonably comprehensive, though it is far from exhaustive. Limited space prevents the inclusion of many significant results. The report is divided into the following sections: Photosphere and Chromosphere; Transition Region; Corona and Coronal Heating; Coronal Jets; Flares; Coronal Mass Ejection Initiation; Global Coronal Waves and Shocks; Coronal Dimming; The Link Between Low Coronal CME Signatures and Magnetic Clouds; Coronal Mass Ejections in the Heliosphere; and Coronal Mass Ejections and Space Weather. Primary authorship is indicated at the beginning of each section.
We argue that it is not possible to infer from the results of Partridge et al. (Reports, 27 January 2006, p. 503) which of their data was taken in the superfluid or normal regime, and which of their clouds are phase-separated and which are not. Some of the conclusions in this paper are inconsistent with recent experiments.