THE PLANCK MISSION: RECENT RESULTS, COSMOLOGICAL AND FUNDAMENTAL PHYSICS PERSPECTIVES

2013 ◽  
Vol 22 (14) ◽  
pp. 1330029
Author(s):  
NAZZARENO MANDOLESI ◽  
CARLO BURIGANA ◽  
ALESSANDRO GRUPPUSO ◽  
PAOLO NATOLI
Keyword(s):  
Polarization Data ◽  
Fundamental Physics ◽  
Parity Symmetry ◽  
And Performance ◽  
Observational Strategy ◽  
Planck Satellite ◽  
Key Questions

We provide a description of the latest status and performance of the Planck satellite, focusing on the final predicted sensitivity of Planck. The optimization of the observational strategy for the additional surveys following the nominal 15 months of integration (about two surveys) originally allocated and the limitation represented by astrophysical foreground emissions are presented. An outline of early and intermediate astrophysical results from the Planck Collaboration is provided. A concise view of some fundamental cosmological results that will be achieved by exploiting Planck's full set of temperature and polarization data are presented. Finally, the perspectives opened by Planck in answering some key questions in fundamental physics, with particular attention to parity symmetry analyses, are described.

Reconsidering Joyce's Exiles in its Theatrical Context

2003 ◽  
Vol 28 (2) ◽  
pp. 169-180 ◽  
Author(s):  
KIRSTEN SHEPHERD-BARR
Keyword(s):  
Fin De Siecle ◽  
Fin De Siècle ◽  
Experimental Theatre ◽  
And Performance ◽  
Key Questions

James Joyce's one extant play, Exiles, has never been held in great critical esteem. But rather than viewing it as an aberration in the Joyce canon, a fairer reading of the play takes into consideration the play's own theatrical context: what contemporary dramatists were doing both in print and on stage, what evidence there is of Joyce's own theatrical interests and what models he may have used in his own playwriting. The conclusion is that Joyce, surprisingly, wrote neither a ‘bad’ Edwardian play nor a slavishly Ibsenist one, but a pastiche of Victorian and Symbolist drama that roots the play firmly in the theatrical currents of the 1890s. In addition, Harold Pinter's landmark productions of the play in 1970 and 1971 revealed affinities with postmodernist drama, so that the play looks forward as well as back – it is simply not of its own time. If Exiles seems out of step with the developments of modernism, that is largely because it takes its inspiration from the European experimental theatre of the fin de siécle – not from the theatrical world of the Dadaists, Joyce's contemporaries. While this realization may not rehabilitate Exiles into the modernist canon or indeed the theatrical one, looking at the play's context and history raises key questions about the role of theatre and performance in the historiography of modernism.

Transport in Stochastic Fibrous Networks

2000 ◽  
Vol 123 (1) ◽  
pp. 12-19 ◽  
Author(s):  
X. Cheng ◽  
A. M. Sastry ◽  
B. E. Layton
Keyword(s):  
Volume Fraction ◽  
High Surface ◽  
High Surface Area ◽  
Statistical Technique ◽  
Porous Structures ◽  
Fibrous Materials ◽  
Aspect Ratios ◽  
And Performance ◽  
2D Network ◽  
Key Questions

Some fundamental issues concerning the design and performance of stochastic porous structures are examined, stemming from application of advanced fibrous electrode substrates in NiMH automotive cells. These electrodes must resist corrosion and local failures under hundreds of charge/discharge cycles. Such fibrous materials can be effectively used as substrates for chemical reactions because of their combinations of high surface area and high conductivity. Key questions concerning the relationships among connectivity and conductivity, scale and variability in material response are addressed. Two techniques are developed and compared for use in predicting these materials’ conductivity. The first approach uses a statistical technique in conjunction with an adaptation of classic micromechanical models. The second approach uses the statistical generation technique, followed by an exact calculation of 2D network conductivity. The two techniques are compared with one another and with classic results. Several important conclusions about the design of these materials are presented, including the importance of use of fibers with aspect ratios greater than at least 50, the weak effect of moderate alignment for unidirectional conductivity, and the weak power-law behavior of conductivity versus volume fraction over the range of possible behaviors.

NEW CONSTRAINTS ON FEATURES IN THE PRIMORDIAL SPECTRUM

2013 ◽  
Vol 23 ◽  
pp. 345-349
Author(s):  
MICOL BENETTI
Keyword(s):  
Cosmic Microwave Background ◽  
Small Amplitude ◽  
Current Data ◽  
Microwave Background ◽  
Polarization Data ◽  
Satellite Mission ◽  
The One ◽  
Planck Satellite

We study a particular inflation models with a small-amplitude step-like feature in the inflaton potential as introducted by Adams et al. and we constraints it with data from the WMAP7 and ACT Cosmic Microwave Background experiments. Also we show that the possibility of a step in the inflationary potential like the one preferred by current data will soon be tested by the forthcoming temperature and polarization data from the Planck satellite mission.

The low frequency instrument on-board the Planck satellite: Characteristics and performance

2007 ◽  
Vol 51 (3-4) ◽  
pp. 287-297 ◽  
Author(s):  
L. Valenziano ◽  
M. Sandri ◽  
G. Morgante ◽  
C. Burigana ◽  
M. Bersanelli ◽  
...  
Keyword(s):  
Low Frequency ◽  
And Performance ◽  
Planck Satellite

scholarly journals Fundamental Physics from Space and in Space

1997 ◽  
Vol 12 (15) ◽  
pp. 2623-2638 ◽  
Author(s):  
M. Jacob
Keyword(s):  
Cosmic Rays ◽  
Gravitational Waves ◽  
Particle Physics ◽  
Astroparticle Physics ◽  
Fundamental Physics ◽  
Key Questions

Whereas most of the key questions in particle physics are still addressed with accelerators, one sees at present an increasing activity in cosmic rays, based on the use of large and sophisticated detectors on the ground and underground (or under water). A new discipline, "astroparticle physics" is born and rapidly expanding. Whereas much of this research is carried out on Earth, it is likely that part of it will eventually transfer to space. The detection of gravitational waves is now attempted with a new promising vigor, using interferometers. This physics at present on the ground will have to extend to space. The talk reviews facts and trends in this research in fun damental physics from space now, but increasingly in space later on.

Magnetic-field strengths from optical polarization data

1967 ◽  
Vol 31 ◽  
pp. 381-383
Author(s):  
J. M. Greenberg
Keyword(s):  
Magnetic Field ◽  
Optical Polarization ◽  
Polarization Data ◽  
Term Model ◽  
Source Of Information ◽  
Field Strengths

Van de Hulst (Paper 64, Table 1) has marked optical polarization as a questionable or marginal source of information concerning magnetic field strengths. Rather than arguing about this–I should rate this method asq+-, or quarrelling about the term ‘model-sensitive results’, I wish to stress the historical point that as recently as two years ago there were still some who questioned that optical polarization was definitely due to magnetically-oriented interstellar particles.

Transmission Scanning Electron Microscopy and Energy Analysis with the Siemens ELMISKOP 101

1972 ◽  
Vol 30 ◽  
pp. 450-451
Author(s):  
H. M. Thieringer
Keyword(s):  
Objective Lens ◽  
Transmission Microscopy ◽  
Image Recording ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
And Performance ◽  
Convergent Beam ◽  
Ray Path ◽  
Beam Diffraction

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.

Angular Resolved Electron Spectroscopy with Parallel Recording

1990 ◽  
Vol 48 (2) ◽  
pp. 370-371
Author(s):  
Huang Min ◽  
P.S. Flora ◽  
C.J. Harland ◽  
J.A. Venables
Keyword(s):  
Electron Spectroscopy ◽  
Low Voltage ◽  
Solid Angle ◽  
Detection System ◽  
Voltage Electron ◽  
Cylindrical Mirror ◽  
Inner Radius ◽  
Channel Plate ◽  
And Performance ◽  
Type Detector

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

Trace nanoanalysis

1994 ◽  
Vol 52 ◽  
pp. 940-941
Author(s):  
D. E. Newbury ◽  
R. D. Leapman
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Detection Efficiency ◽  
Volume Element ◽  
And Performance ◽  
Trace Constituents ◽  
Secondary Ion ◽  
Concentration Levels ◽  
Structure Properties

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).

Sign in / Sign up

Export Citation Format

Share Document