Journal: Monthly Notices of the Royal Astronomical Society

Abbreviation

Mon. Not. R. Astron. Soc.

Publisher

Oxford University Press

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ISSN

0035-8711
1365-2966

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Publications1 - 10 of 668
  • Probing the very high energy γ-ray spectral curvature in the blazar PG 1553+113 with the MAGIC telescopes
    Item type: Journal Article
    MAGIC Collaboration; Fermi-LAT Collaboration; Aleksić, Jelena; et al. (2015)
    Monthly Notices of the Royal Astronomical Society
  • Two warm Neptunes transiting HIP 9618 revealed by TESS and Cheops
    Item type: Journal Article
    Osborn, Hugh P.; Nowak, G.; Hébrard, Guillaume; et al. (2023)
    Monthly Notices of the Royal Astronomical Society
    HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R (HIP 9618 b) and 3.343 ± 0.039 R (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a 680-d gap in the time series, leaving many possibilities for the period. To solve this issue, CHEOPS performed targeted photometry of period aliases to attempt to recover the true period of planet c, and successfully determined the true period to be 52.56349 d. High-resolution spectroscopy with HARPS-N, SOPHIE, and CAFE revealed a mass of 10.0 ± 3.1M for HIP 9618 b, which, according to our interior structure models, corresponds to a 6.8 ± 1.4 per cent gas fraction. HIP 9618 c appears to have a lower mass than HIP 9618 b, with a 3-sigma upper limit of <18M. Follow-up and archival RV measurements also reveal a clear long-term trend which, when combined with imaging and astrometric information, reveal a low-mass companion (0.08+−000512M☉) orbiting at 26.0+−111900 au. This detection makes HIP 9618 one of only five bright (K < 8 mag) transiting multiplanet systems known to host a planet with P > 50 d, opening the door for the atmospheric characterization of warm (Teq < 750 K) sub-Neptunes.
  • Noise bias in weak lensing shape measurements
    Item type: Journal Article
    Refregier, Alexandre; Kacprzak, Tomasz; Amara, Adam; et al. (2012)
    Monthly Notices of the Royal Astronomical Society
  • BIRTH of the COSMOS field: Primordial and evolved density reconstructions during cosmic high noon
    Item type: Journal Article
    Ata, Metin; Kitaura, Francisco-Shu; Lee, Khee-Gan; et al. (2021)
    Monthly Notices of the Royal Astronomical Society
    This work presents the first comprehensive study of structure formation at the peak epoch of cosmic star formation over 1.4 ≤ z ≤ 3.6 in the Cosmic Evolution Survey (COSMOS) field, including the most massive high-redshift galaxy proto-clusters at that era. We apply the extended COSMIC BIRTH algorithm to account for a multitracer and multisurvey Bayesian analysis at Lagrangian initial cosmic times. Combining the data of five different spectroscopic redshift surveys (zCOSMOS-deep, VUDS, MOSDEF, ZFIRE, and FMOS–COSMOS), we show that the corresponding unbiased primordial density fields can be inferred, if a proper survey completeness computation from the parent photometric catalogues, and a precise treatment of the non-linear and non-local evolution on the light-cone is taken into account, including (i) gravitational matter displacements, (ii) peculiar velocities, and (iii) galaxy bias. The reconstructions reveal a holistic view on the known proto-clusters in the COSMOS field and the growth of the cosmic web towards lower redshifts. The inferred distant dark matter density fields concurrently with other probes like tomographic reconstructions of the intergalactic medium will explore the interplay of gas and dark matter and are ideally suited to study structure formation at high redshifts in the light of upcoming deep surveys. © 2021 Oxford University Press
  • Isotopic enrichment of forming planetary systems from supernova pollution
    Item type: Journal Article
    Lichtenberg, Tim; Parker, Richard J.; Meyer, Michael R. (2016)
    Monthly Notices of the Royal Astronomical Society
  • OpenUniverse2024: A shared, simulated view of the sky for the next generation of cosmological surveys
    Item type: Journal Article
    OpenUniverse; The LSST Dark Energy Science Collaboration; The Roman HLIS Project Infrastructure; et al. (2025)
    Monthly Notices of the Royal Astronomical Society
    The OpenUniverse2024 simulation suite is a cross-collaboration effort to produce matched simulated imaging for multiple surveys as they would observe a common simulated sky. Both the simulated data and associated tools used to produce it are intended to uniquely enable a wide range of studies to maximize the science potential of the next generation of cosmological surveys. We have produced simulated imaging for approximately 70 deg2 of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) Wide-Fast-Deep survey and the Nancy Grace Roman Space Telescope High-Latitude Wide-Area Survey, as well as overlapping versions of the ELAIS-S1 Deep-Drilling Field for LSST and the High-Latitude Time-Domain Survey for Roman. OpenUniverse2024 includes (i) an early version of the updated extragalactic model called Diffsky, which substantially improves the realism of optical and infrared photometry of objects, compared to previous versions of these models; (ii) updated transient models that extend through the wavelength range probed by Roman and Rubin; and (iii) improved survey, telescope, and instrument realism based on up-to-date survey plans and known properties of the instruments. It is built on a new and updated suite of simulation tools that improves the ease of consistently simulating multiple observatories viewing the same sky. The approximately 400 TB of synthetic survey imaging and simulated universe catalogs are publicly available, and we preview some scientific uses of the simulations.
  • The impact of spectroscopic incompleteness in direct calibration of redshift distributions for weak lensing surveys
    Item type: Journal Article
    DES Collaboration; Hartley, William G.; et al. (2020)
    Monthly Notices of the Royal Astronomical Society
    Obtaining accurate distributions of galaxy redshifts is a critical aspect of weak lensing cosmology experiments. One of the methods used to estimate and validate redshift distributions is to apply weights to a spectroscopic sample, so that their weighted photometry distribution matches the target sample. In this work, we estimate the selection bias in redshift that is introduced in this procedure. We do so by simulating the process of assembling a spectroscopic sample (including observer-assigned confidence flags) and highlight the impacts of spectroscopic target selection and redshift failures. We use the first year (Y1) weak lensing analysis in Dark Energy Survey (DES) as an example data set but the implications generalize to all similar weak lensing surveys. We find that using colour cuts that are not available to the weak lensing galaxies can introduce biases of up to Delta z similar to 0.04 in the weighted mean redshift of different redshift intervals (Delta z similar to 0.015 in the case most relevant to DES). To assess the impact of incompleteness in spectroscopic samples, we select only objects with high observer-defined confidence flags and compare the weighted mean redshift with the true mean. We find that the mean redshift of the DES Y1 weak lensing sample is typically biased at the Delta z = 0.005-0.05 level after the weighting is applied. The bias we uncover can have either sign, depending on the samples and redshift interval considered. For the highest redshift bin, the bias is larger than the uncertainties in the other DES Y1 redshift calibration methods, justifying the decision of not using this method for the redshift estimations. We discuss several methods to mitigate this bias.
  • Photometric redshift analysis in the Dark Energy Survey Science Verification data
    Item type: Journal Article
    Sánchez, C.; Amara, Adam; Hartley, William G.; et al. (2014)
    Monthly Notices of the Royal Astronomical Society
  • A SINFONI view of the nuclear activity and circumnuclear star formation in NGC 4303 – II. Spatially resolved stellar populations
    Item type: Journal Article
    Dametto, Natacha Z.; Riffel, Rogemar A.; Colina, Luis A.; et al. (2019)
    Monthly Notices of the Royal Astronomical Society
    We present a spatially resolved stellar population study of the inner ∼200 pc radius of NGC 4303 based on near-infrared integral field spectroscopy with SINFONI/VLT at a spatial resolution of 40–80 pc and using the STARLIGHT code. We found that the distribution of the stellar populations presents a spatial variation, suggesting an age stratification. Three main structures stand out. Two nuclear blobs, one composed by young stars (t ≤ 50 Myr) and one with intermediate-age stars (50 Myr < t ≤ 2 Gyr), both shifted from the centre. The third one is an internal intermediate-age spiral arm-like structure, surrounding the blob of young stars. Our results indicate that star formation has occurred through multiple bursts in this source. Furthermore, the youngest stellar populations (t ≲ 2 Gyr) are distributed along a circumnuclear star-forming ring with r ∼ 250 pc. The ring displays star formation rates (SFRs) in the range of 0.002–0.14 M⊙yr⁻¹, favouring the ‘pearls-on-a-string’ scenario. The old underlying bulge stellar population component (t > 2 Gyr) is distributed outside the two blob structures. For the nuclear region (inner ∼60 pc radius) we derived an SFR of 0.43 M⊙ yr⁻¹ and found no signatures of non-thermal featureless continuum and hot dust emission, supporting the scenario in which an LLAGN/LINER-like source is hidden in the centre of NGC 4303. Thus, our results reveal a rather complex star formation history in NGC 4303, with different stellar population components coexisting with a low efficiency accreting black hole in its centre.
  • Bias deconstructed
    Item type: Journal Article
    Paranjape, Aseem; Sefusatti, Emiliano; Chan, Kwan Chuen; et al. (2013)
    Monthly Notices of the Royal Astronomical Society
Publications1 - 10 of 668