A5064190876- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Cosmology and Gravitation Theories
- Superconducting and THz Device Technology
- Radio Astronomy Observations and Technology
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Spacecraft Design and Technology
- Solar and Space Plasma Dynamics
- Spectroscopy and Laser Applications
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Photonic and Optical Devices
- Advanced Antenna and Metasurface Technologies
- Microwave Engineering and Waveguides
- Metamaterials and Metasurfaces Applications
University College London
2016-2025
Centre National de la Recherche Scientifique
2014-2024
Université Paris-Saclay
2022-2024
Institut d'Astrophysique Spatiale
2014-2024
Institut de Recherche en Astrophysique et Planétologie
2024
National University of Ireland
2022
Goddard Space Flight Center
2018-2022
University College Lahore
2021
Cardiff University
2007-2019
UCL Australia
2009-2019
We present a full high resolution SPIRE FTS spectrum of the nearby ultraluminous infrared galaxy Mrk231. In total 25 lines are detected, including CO J=5-4 through J=13-12, 7 rotational H2O, 3 OH+ and one line each H2O+, CH+, HF. find that excitation levels up to J=8 can be accounted for by UV radiation from star formation. However, approximately flat luminosity distribution over ladder above requires presence separate source highest lines. explore X-ray heating accreting supermassive black...
<i>Context. <i/>The High Frequency Instrument (HFI) is one of the two focal instruments <i>Planck<i/> mission. It will observe whole sky in six bands 100 GHz–1 THz range.<i>Aims. HFI instrument designed to measure cosmic microwave background (CMB) with a sensitivity limited only by fundamental sources: photon noise CMB itself and residuals left after removal foregrounds. The high frequency provide full maps submillimetre sky, featuring mainly extended point source Systematic effects must be...
SPIRE, the Spectral and Photometric Imaging REceiver, is <i>Herschel<i/> Space Observatory's submillimetre camera spectrometer. It contains a three-band imaging photometer operating at 250, 350 500 <i>μ<i/>m, an Fourier-transform spectrometer (FTS) covering 194–671 <i>μ<i/>m (447-1550 GHz). In this paper we describe initial approach taken to absolute calibration of SPIRE instrument using combination emission from telescope itself modelled continuum solar system objects other astronomical...
We present a detailed analysis of the far-IR properties bright, lensed, z = 2.3, SMG, SMM J2135-0102, using new observations with Herschel, SCUBA-2 and VLA. These data allow us to constrain galaxy's SED show that it has an intrinsic rest-frame 8-1000um luminosity, L(bol), (2.3 +/- 0.2) x 10^12 L(sun) likely SFR ~400 M(sun)/yr. The galaxy sits on far-IR/radio correlation for far-IR-selected galaxies. At ~>70um, can be described adequately by dust components T(d) ~ 30 60K. Using SPIRE's...
We present results for Vela C obtained during the 2012 flight of Balloon-borne Large Aperture Submillimeter Telescope Polarimetry (BLASTPol). mapped polarized intensity across almost entire extent this giant molecular cloud, in bands centered at 250, 350, and 500 {\mu}m. In initial paper, we show our {\mu}m data smoothed to a resolution 2.5 arcminutes (approximately 0.5 pc). that mean level fractional polarization p most its spatial variations can be accounted using an empirical...
We present the first results from B-fields In STar-forming Region Observations (BISTRO) survey, using Sub-millimetre Common-User Bolometer Array 2 (SCUBA-2) camera, with its associated polarimeter (POL-2), on James Clerk Maxwell Telescope (JCMT) in Hawaii. discuss survey's aims and objectives. describe rationale behind questions which survey will aim to answer. The most important of these is role magnetic fields star formation process scale individual filaments cores dense regions. data...
The prototype of the NIKA2 camera, NIKA, is an instrument operating at IRAM 30-m telescope, which can observe simultaneously 150 and 260GHz. One main goals to measure pressure distribution in galaxy clusters high resolution using thermal SZ (tSZ) effect. Such observations have already proved be excellent probe cluster distributions even redshifts. However, important fraction host submm and/or radio point sources, significantly affect reconstructed signal. Here we report on <20" 260GHz...
Abstract We study the possibility of using LiteBIRD satellite B -mode survey to constrain models inflation producing specific features in CMB angular power spectra. explore a particular model example, i.e. spectator axion-SU(2) gauge field inflation. This can source parity-violating gravitational waves from amplification fluctuations driven by pseudoscalar “axionlike” field, rolling for few e-folds during The sourced exceed vacuum contribution at reionization bump scales about an order...
We statistically evaluate the relative orientation between gas column density structures, inferred from Herschel submillimetre observations, and magnetic field projected on plane of sky, polarized thermal emission Galactic dust observed by BLASTPol at 250, 350, 500 micron, towards Vela C molecular complex. First, we find very good agreement polarization orientations in three wavelength-bands, suggesting that, considered common angular resolution 3.0 arcminutes that corresponds to a physical...
The POL-2 polarimeter for the SCUBA-2 10 000 pixel Terahertz camera on James Clerk Maxwell Telescope (JCMT) in it's late state of commissioning. Proposals have been accepted and general observing will start August 2016. has a field view 43 arcmin at both 850 450 μm focal planes. map sky band. utilizes three optical components: half wave plate two wire-grid polarizers used as calibrator analyzer covering full SCUBA-2. We describe instrument, data acquisition features/artifacts that encountered during
The High Frequency Instrument of <i>Planck<i/> will map the entire sky in millimeter and sub-millimeter domain from 100 to 857 GHz with unprecedented sensitivity polarization (Δ<i>P<i/>/<i>T<i/><sub>cmb<sub/> ~ 4 × 10<sup>-6<sup/> for <i>P<i/> either <i>Q<i/> or <i>U<i/> <i>T<i/><sub>cmb<sub/> 2.7 K) at 100, 143, 217 353 GHz. It lead major improvements our understanding cosmic microwave background anisotropies polarized foreground signals. make high resolution measurements <i>E<i/>-mode...
<i>Planck<i/> is a scientific satellite that represents the next milestone in space-based research related to cosmic microwave background, and many other astrophysical fields. was launched on 14 May of 2009 now operational. The uncertainty optical response its detectors key factor allowing achieve objectives. More than decade analysis measurements have gone into achieving required performances. In this paper, we describe main aspects optics are relevant science, estimated in-flight...
The Ultra Luminous InfraRed Galaxy Mrk 231 reveals up to seven rotational lines of water (H2O) in emission, including a very high-lying (E_{upper}=640 K) line detected at 4sigma level, within the Herschel/SPIRE wavelength range, whereas PACS observations show one H2O 78 microns absorption, as found for other previously by ISO. absorption/emission dichotomy is caused pumping levels far-infrared radiation emitted dust, and subsequent relaxation through longer wavelengths, which allows us...
We present the results of dust emission polarization measurements Ophiuchus-B (Oph-B) carried out using Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera with its associated polarimeter (POL-2) on James Clerk Maxwell Telescope (JCMT) in Hawaii. This work is part B-fields In Star-forming Region Observations (BISTRO) survey initiated to understand role magnetic fields star formation for nearby star-forming molecular clouds. a first look at geometry and strength Oph-B. The field...
Clusters of galaxies provide valuable information on the evolution Universe and large scale structures. Recent cluster observations via thermal Sunyaev-Zel'dovich (tSZ) effect have proven to be a powerful tool detect study them. In this context, high resolution tSZ (~ tens arcsec) are particular interest probe intermediate redshift clusters. Observations will carried out with millimeter dual-band NIKA2 camera, based Kinetic Inductance Detectors (KIDs) installed at IRAM 30-meter telescope in...
The New IRAM KID Array (NIKA) instrument is a dual-band imaging camera operating with Kinetic Inductance Detectors (KID) cooled at 100 mK. NIKA designed to observe the sky wavelengths of 1.25 and 2.14 mm from 30 m telescope Pico Veleta an estimated resolution 13\,arcsec 18 arcsec, respectively. This work presents performance prior its opening astrophysical community as common-user facility in early 2014. test bench for final NIKA2 be installed end 2015. last observation campaigns on November...
Abstract We present 850 μ m imaging polarimetry data of the ρ Oph-A core taken with Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part our ongoing survey project, <?CDATA ${\boldsymbol{B}}$?> -fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify orientation magnetic field projected on plane sky at a resolution 0.01 pc. 10 subregions distinct fractions angles in 0.2 pc core; some them can be coherent structure Oph...
LiteBIRD is a planned JAXA-led CMB B-mode satellite experiment aiming for launch in the late 2020s, with primary goal of detecting imprint primordial inflationary gravitational waves. Its current baseline focal-plane configuration includes 15 frequency bands between 40 and 402 GHz, fulfilling mission requirements to detect amplitude waves total uncertainty on tensor-to-scalar ratio, $\delta r$, down r<0.001$. A key aspect this performance accurate astrophysical component separation, ability...
We describe a novel artificial dielectric material which has applications at millimetre and submillimetre wavelengths. The is manufactured from layers of metal mesh patterned onto thin polypropylene sheets are then bonded together using hot pressing process to provide planar rugged discs can be reliably cycled cryogenic temperatures. refractive index this tuned by adjusting the geometry spacing metal-mesh layers. demonstrate its usage designing characterising broadband anti-reflection...
The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was created by adding polarimetric capability to the BLAST experiment that flown in 2003, 2005, and 2006. BLASTPol inherited BLAST's 1.8 m primary its Herschel/SPIRE heritage focal plane allows simultaneous observation at 250, 350, 500 {\mu}m. We flew 2010 again 2012. Both were long duration Antarctic flights. Here we present polarimetry of nearby filamentary dark cloud Lupus I obtained during flight. Despite...
The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was a suborbital experiment designed to map magnetic fields in order study their role star formation processes. BLASTPol made detailed polarization maps of number molecular clouds during its successful flights from Antarctica 2010 and 2012. We present the next-generation instrument (BLAST-TNG) that will build off success previous continue as unique test bed new technologies. With 16-fold increase mapping...