28 research outputs found
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Abdominal and iliac arterial stenoses: comparative double-blinded randomized study of diagnostic accuracy of 3D MR angiography with gadodiamide or gadopentetate dimeglumine.
International audiencePURPOSE: To prospectively evaluate accuracy of gadolinium-enhanced three-dimensional (3D) magnetic resonance (MR) angiography with gadodiamide and gadopentetate dimeglumine (0.1 mmol/kg), with intraarterial DSA as reference standard, for imaging abdominal and iliac arterial stenoses. MATERIALS AND METHODS: The study was approved by all institutional review boards; informed consent was obtained from each subject before procedures. Two hundred forty-seven subjects were included; 240 received either contrast agent and were available for safety analysis; 222 were available for accuracy analysis. Enhanced 3D MR angiography and DSA were performed; image data were evaluated in a double-blinded randomized study. Stenoses were classified as not relevant ( or =50%). For detection of main stenosis, accuracy with enhanced 3D MR angiography compared with that with DSA was determined. RESULTS: The difference in accuracy for imaging with gadodiamide and gadopentetate was 3.6%. Noninferiority was inferred because the lower bound of the exact two-sided 95% confidence interval was -10.1 and was above the noninferiority margin (-15%). Accuracy for detection of the main stenosis was low, 56.4% for gadodiamide and 52.8% for gadopentetate group. Subgroup analysis with exclusion of inferior mesenteric artery and internal iliac arteries and the most false-positive stenosis classifications yielded better results: 76.6% and 71.6%, respectively. Sensitivity, specificity, and negative and positive predictive values did not differ substantially between study groups. In the main analysis, values were 44%, 96%, 35%, and 97% for gadodiamide and 44%, 83%, 30%, and 90% for gadopentetate, respectively. In the subgroup analysis, values were 66%, 95%, 61%, and 96% for gadodiamide and 63%, 86%, 58%, and 88% for gadopentetate, respectively. CONCLUSION: Noninferiority of gadodiamide versus gadopentetate was verified based on the primary end point, which was accuracy for detection of the main stenosis with enhanced 3D MR angiography compared with DSA
Abdominal and Iliac Arterial Stenoses: Comparative Double-blinded Randomized Study of Diagnostic Accuracy of 3D MR Angiography with Gadodiamide or Gadopentetate Dimeglumine
PRISM (Polarized Radiation Imaging and Spectroscopy Mission): an extended white paper
Contains fulltext :
126057.pdf (preprint version ) (Open Access
The Herschel-SPIRE Legacy Survey (HSLS): the scientific goals of a shallow and wide submillimeter imaging survey with SPIRE
A large sub-mm survey with Herschel will enable many exciting science opportunities, especially in an era of wide-field optical and radio surveys and high resolution cosmic microwave background experiments. The Herschel-SPIRE Legacy Survey (HSLS), will lead to imaging data over 4000 sq. degrees at 250, 350, and 500 micron. Major Goals of HSLS are: (a) produce a catalog of 2.5 to 3 million galaxies down to 26, 27 and 33 mJy (50% completeness; 5 sigma confusion noise) at 250, 350 and 500 micron, respectively, in the southern hemisphere (3000 sq. degrees) and in an equatorial strip (1000 sq. degrees), areas which have extensive multi-wavelength coverage and are easily accessible from ALMA. Two thirds of the of the sources are expected to be at z > 1, one third at z > 2 and about a 1000 at z > 5. (b) Remove point source confusion in secondary anisotropy studies with Planck and ground-based CMB data. (c) Find at least 1200 strongly lensed bright sub-mm sources leading to a 2% test of general relativity. (d) Identify 200 proto-cluster regions at z of 2 and perform an unbiased study of the environmental dependence of star formation. (e) Perform an unbiased survey for star formation and dust at high Galactic latitude and make a census of debris disks and dust around AGB stars and white dwarfs
Erratum: Planck 2018 results: VI. Cosmological parameters (Astronomy and Astrophysics (2020) 641 (A6) DOI: 10.1051/0004-6361/201833910)
none181In the original version, the bounds given in Eqs. (87a) and (87b) on the contribution to the early-time optical depth, (15,30), contained a numerical error in deriving the 95th percentile from the Monte Carlo samples. The corrected 95% upper bounds are: τ(15,30) < 0:018 (lowE, flat τ(15, 30), FlexKnot), (1) τ(15, 30) < 0:023 (lowE, flat knot, FlexKnot): (2) These bounds are a factor of 3 larger than the originally reported results. Consequently, the new bounds do not significantly improve upon previous results from Planck data presented in Millea & Bouchet (2018) as was stated, but are instead comparable. Equations (1) and (2) give results that are now similar to those of Heinrich & Hu (2021), who used the same Planck 2018 data to derive a 95% upper bound of 0.020 using the principal component analysis (PCA) model and uniform priors on the PCA mode amplitudes.noneAghanim N.; Akrami Y.; Ashdown M.; Aumont J.; Baccigalupi C.; Ballardini M.; Banday A.J.; Barreiro R.B.; Bartolo N.; Basak S.; Battye R.; Benabed K.; Bernard J.-P.; Bersanelli M.; Bielewicz P.; Bock J.J.; Bond J.R.; Borrill J.; Bouchet F.R.; Boulanger F.; Bucher M.; Burigana C.; Butler R.C.; Calabrese E.; Cardoso J.-F.; Carron J.; Challinor A.; Chiang H.C.; Chluba J.; Colombo L.P.L.; Combet C.; Contreras D.; Crill B.P.; Cuttaia F.; De Bernardis P.; De Zotti G.; Delabrouille J.; Delouis J.-M.; DI Valentino E.; DIego J.M.; Dore O.; Douspis M.; Ducout A.; Dupac X.; Dusini S.; Efstathiou G.; Elsner F.; Ensslin T.A.; Eriksen H.K.; Fantaye Y.; Farhang M.; Fergusson J.; Fernandez-Cobos R.; Finelli F.; Forastieri F.; Frailis M.; Fraisse A.A.; Franceschi E.; Frolov A.; Galeotta S.; Galli S.; Ganga K.; Genova-Santos R.T.; Gerbino M.; Ghosh T.; Gonzalez-Nuevo J.; Gorski K.M.; Gratton S.; Gruppuso A.; Gudmundsson J.E.; Hamann J.; Handley W.; Hansen F.K.; Herranz D.; Hildebrandt S.R.; Hivon E.; Huang Z.; Jaffe A.H.; Jones W.C.; Karakci A.; Keihanen E.; Keskitalo R.; Kiiveri K.; Kim J.; Kisner T.S.; Knox L.; Krachmalnicoff N.; Kunz M.; Kurki-Suonio H.; Lagache G.; Lamarre J.-M.; Lasenby A.; Lattanzi M.; Lawrence C.R.; Le Jeune M.; Lemos P.; Lesgourgues J.; Levrier F.; Lewis A.; Liguori M.; Lilje P.B.; Lilley M.; Lindholm V.; Lopez-Caniego M.; Lubin P.M.; Ma Y.-Z.; MacIas-Perez J.F.; Maggio G.; Maino D.; Mandolesi N.; Mangilli A.; Marcos-Caballero A.; Maris M.; Martin P.G.; Martinelli M.; Martinez-Gonzalez E.; Matarrese S.; Mauri N.; McEwen J.D.; Meinhold P.R.; Melchiorri A.; Mennella A.; Migliaccio M.; Millea M.; Mitra S.; Miville-Deschenes M.-A.; Molinari D.; Montier L.; Morgante G.; Moss A.; Natoli P.; Norgaard-Nielsen H.U.; Pagano L.; Paoletti D.; Partridge B.; Patanchon G.; Peiris H.V.; Perrotta F.; Pettorino V.; Piacentini F.; Polastri L.; Polenta G.; Puget J.-L.; Rachen J.P.; Reinecke M.; Remazeilles M.; Renzi A.; Rocha G.; Rosset C.; Roudier G.; Rubino-Martin J.A.; Ruiz-Granados B.; Salvati L.; Sandri M.; Savelainen M.; Scott D.; Shellard E.P.S.; Sirignano C.; Sirri G.; Spencer L.D.; Sunyaev R.; Suur-Uski A.-S.; Tauber J.A.; Tavagnacco D.; Tenti M.; Toffolatti L.; Tomasi M.; Trombetti T.; Valenziano L.; Valiviita J.; Van Tent B.; Vibert L.; Vielva P.; Villa F.; Vittorio N.; Wandelt B.D.; Wehus I.K.; White M.; White S.D.M.; Zacchei A.; Zonca A.Aghanim, N.; Akrami, Y.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Ballardini, M.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Basak, S.; Battye, R.; Benabed, K.; Bernard, J. -P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J. -F.; Carron, J.; Challinor, A.; Chiang, H. C.; Chluba, J.; Colombo, L. P. L.; Combet, C.; Contreras, D.; Crill, B. P.; Cuttaia, F.; De Bernardis, P.; De Zotti, G.; Delabrouille, J.; Delouis, J. -M.; DI Valentino, E.; Diego, J. M.; Dore, O.; Douspis, M.; Ducout, A.; Dupac, X.; Dusini, S.; Efstathiou, G.; Elsner, F.; Ensslin, T. A.; Eriksen, H. K.; Fantaye, Y.; Farhang, M.; Fergusson, J.; Fernandez-Cobos, R.; Finelli, F.; Forastieri, F.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frolov, A.; Galeotta, S.; Galli, S.; Ganga, K.; Genova-Santos, R. T.; Gerbino, M.; Ghosh, T.; Gonzalez-Nuevo, J.; Gorski, K. M.; Gratton, S.; Gruppuso, A.; Gudmundsson, J. E.; Hamann, J.; Handley, W.; Hansen, F. K.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Huang, Z.; Jaffe, A. H.; Jones, W. C.; Karakci, A.; Keihanen, E.; Keskitalo, R.; Kiiveri, K.; Kim, J.; Kisner, T. S.; Knox, L.; Krachmalnicoff, N.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J. -M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Le Jeune, M.; Lemos, P.; Lesgourgues, J.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Lilley, M.; Lindholm, V.; Lopez-Caniego, M.; Lubin, P. M.; Ma, Y. -Z.; MacIas-Perez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Marcos-Caballero, A.; Maris, M.; Martin, P. G.; Martinelli, M.; Martinez-Gonzalez, E.; Matarrese, S.; Mauri, N.; Mcewen, J. D.; Meinhold, P. R.; Melchiorri, A.; Mennella, A.; Migliaccio, M.; Millea, M.; Mitra, S.; Miville-Deschenes, M. -A.; Molinari, D.; Montier, L.; Morgante, G.; Moss, A.; Natoli, P.; Norgaard-Nielsen, H. U.; Pagano, L.; Paoletti, D.; Partridge, B.; Patanchon, G.; Peiris, H. V.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Polastri, L.; Polenta, G.; Puget, J. -L.; Rachen, J. P.; Reinecke, M.; Remazeilles, M.; Renzi, A.; Rocha, G.; Rosset, C.; Roudier, G.; Rubino-Martin, J. A.; Ruiz-Granados, B.; Salvati, L.; Sandri, M.; Savelainen, M.; Scott, D.; Shellard, E. P. S.; Sirignano, C.; Sirri, G.; Spencer, L. D.; Sunyaev, R.; Suur-Uski, A. -S.; Tauber, J. A.; Tavagnacco, D.; Tenti, M.; Toffolatti, L.; Tomasi, M.; Trombetti, T.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vibert, L.; Vielva, P.; Villa, F.; Vittorio, N.; Wandelt, B. D.; Wehus, I. K.; White, M.; White, S. D. M.; Zacchei, A.; Zonca, A