GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    A blast from the infant Universe: The very high- z GRB 210905A
    EDP Sciences ; 2022
    In:  Astronomy & Astrophysics Vol. 665 ( 2022-09), p. A125-
    Details
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 665 ( 2022-09), p. A125-
    Abstract: We present a detailed follow-up of the very energetic GRB 210905A at a high redshift of z  = 6.312 and its luminous X-ray and optical afterglow. Following the detection by Swift and Konus- Wind , we obtained a photometric and spectroscopic follow-up in the optical and near-infrared (NIR), covering both the prompt and afterglow emission from a few minutes up to 20 Ms after burst. With an isotropic gamma-ray energy release of E iso = 1.27 −0.19 +0.20 × 10 54 erg, GRB 210905A lies in the top ∼7% of gamma-ray bursts (GRBs) in the Konus- Wind catalogue in terms of energy released. Its afterglow is among the most luminous ever observed, and, in particular, it is one of the most luminous in the optical at t  ≳ 0.5 d in the rest frame. The afterglow starts with a shallow evolution that can be explained by energy injection, and it is followed by a steeper decay, while the spectral energy distribution is in agreement with slow cooling in a constant-density environment within the standard fireball theory. A jet break at ∼46.2 ± 16.3 d (6.3 ± 2.2 d rest-frame) has been observed in the X-ray light curve; however, it is hidden in the H band due to a constant contribution from the host galaxy and potentially from a foreground intervening galaxy. In particular, the host galaxy is only the fourth GRB host at z   〉  6 known to date. By assuming a number density n  = 1 cm −3 and an efficiency η  = 0.2, we derived a half-opening angle of 8.4 ° ±1.0°, which is the highest ever measured for a z  ≳ 6 burst, but within the range covered by closer events. The resulting collimation-corrected gamma-ray energy release of ≃1 × 10 52 erg is also among the highest ever measured. The moderately large half-opening angle argues against recent claims of an inverse dependence of the half-opening angle on the redshift. The total jet energy is likely too large to be sustained by a standard magnetar, and it suggests that the central engine of this burst was a newly formed black hole. Despite the outstanding energetics and luminosity of both GRB 210905A and its afterglow, we demonstrate that they are consistent within 2 σ with those of less distant bursts, indicating that the powering mechanisms and progenitors do not evolve significantly with redshift.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    URL: Article
    DOI: 10.1051/0004-6361/202243225
    RVK:
    UA 1000
    RVK:
    US 1090
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2022
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    The ALMA-ALPINE [CII] survey : The star formation history and the dust emission of star-forming galaxies at 4.5 〈 z 〈 6.2
    EDP Sciences ; 2022
    In:  Astronomy & Astrophysics Vol. 664 ( 2022-08), p. A73-
    Details
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 664 ( 2022-08), p. A73-
    Abstract: Star-forming galaxies are composed of various types of galaxies. However, the luminosity functions at z  ≳ 4–5 suggest that most galaxies have a relatively low stellar mass (log M star  ∼ 10) and a low dust attenuation ( A FUV  ∼ 1.0). The physical properties of these objects are quite homogeneous. We used an approach where we combined their rest-frame far-infrared and submillimeter emissions and utilized the universe and the redshift as a spectrograph to increase the amount of information in a collective way. From a subsample of 27 ALMA-detected galaxies at z   〉  4.5, we built an infrared spectral energy distribution composite template. It was used to fit, with CIGALE, the 105 galaxies (detections and upper limits) in the sample from the far-ultraviolet to the far-infrared. The derived physical parameters provide information to decipher the nature of the dust cycle and of the stellar populations in these galaxies. The derived IR composite template is consistent with the galaxies in the studied sample. A delayed star formation history with τ main  = 500 Myr is slightly favored by the statistical analysis as compared to a delayed with a final burst or a continuous star formation history. The position of the sample in the star formation rate (SFR) versus M star diagram is consistent with previous papers. The redshift evolution of the log M star versus A FUV relation is in agreement with an evolution in redshift of this relation. This evolution is necessary to explain the cosmic evolution of the average dust attenuation of galaxies. Evolution is also observed in the L dust / L FUV (IRX) versus UV slope β FUV diagram: younger galaxies have bluer β FUV . We modeled the shift of galaxies in the IRX versus the β FUV diagram with the mass-weighted age as a free parameter, and we provide an equation to make predictions. The large sample studied in this paper is generally consistent with models that assume rapid dust formation from supernovae and removal of dust by outflows and supernovae blasts. However, we find that high mass dusty star-forming galaxies cannot be explained by the models.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    URL: Article
    DOI: 10.1051/0004-6361/202142554
    RVK:
    UA 1000
    RVK:
    US 1090
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2022
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    CEERS Key Paper. VI. JWST/MIRI Uncovers a Large Population of Obscured AGN at High Redshifts
    American Astronomical Society ; 2023
    In:  The Astrophysical Journal Letters Vol. 950, No. 1 ( 2023-06-01), p. L5-
    Details
    In: The Astrophysical Journal Letters, American Astronomical Society, Vol. 950, No. 1 ( 2023-06-01), p. L5-
    Abstract: Mid-infrared (mid-IR) observations are powerful in identifying heavily obscured active galactic nuclei (AGN) that have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope provides an excellent opportunity to perform such studies. We take advantage of the MIRI imaging data from the Cosmic Evolution Early Release Science Survey to investigate the AGN population in the distant universe. We estimate the source properties of MIRI-selected objects by utilizing spectral energy distribution (SED) modeling, and classify them into star-forming galaxies (SFs), SF-AGN mixed objects, and AGN. The source numbers of these types are 433, 102, and 25, respectively, from four MIRI pointings covering ∼9 arcmin 2 . The sample spans a redshift range of ≈0–5. We derive the median SEDs for all three source types, respectively, and publicly release them. The median MIRI SED of AGN is similar to the typical SEDs of hot dust-obscured galaxies and Seyfert 2s, for which the mid-IR SEDs are dominated by emission from AGN-heated hot dust. Based on our SED-fit results, we estimate the black hole accretion density (BHAD; i.e., total BH growth rate per comoving volume) as a function of redshift. At z 〈 3, the resulting BHAD agrees with the X-ray measurements in general. At z 〉 3, we identify a total of 27 AGN and SF-AGN mixed objects, leading to that our high- z BHAD is substantially higher than the X-ray results (∼0.5 dex at z ≈ 3–5). This difference indicates MIRI can identify a large population of heavily obscured AGN missed by X-ray surveys at high redshifts.
    Type of Medium: Online Resource
    ISSN: 2041-8205 , 2041-8213
    URL: Article
    DOI: 10.3847/2041-8213/acd639
    Language: Unknown
    Publisher: American Astronomical Society
    Publication Date: 2023
    detail.hit.zdb_id: 2207648-7
    detail.hit.zdb_id: 2006858-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Origins space telescope: from first light to life
    Springer Science and Business Media LLC ; 2021
    In:  Experimental Astronomy Vol. 51, No. 3 ( 2021-06), p. 595-624
    Details
    In: Experimental Astronomy, Springer Science and Business Media LLC, Vol. 51, No. 3 ( 2021-06), p. 595-624
    Abstract: The Origins Space Telescope (Origins) is one of four science and technology definition studies selected by the National Aeronautics and Space Administration (NASA) in preparation of the 2020 Astronomy and Astrophysics Decadal survey in the US. Origins will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. It is designed to answer three major science questions: How do galaxies form stars, make metals, and grow their central supermassive black holes from reionization? How do the conditions for habitability develop during the process of planet formation? Do planets orbiting M-dwarf stars support life? Origins operates at mid- to far-infrared wavelengths from ~ 2.8 μm to 588 μm, and is more than 1000 times more sensitive than prior far-IR missions due to its cold (~ 4.5 K) aperture and state-of-the-art instruments.
    Type of Medium: Online Resource
    ISSN: 0922-6435 , 1572-9508
    URL: Article
    DOI: 10.1007/s10686-021-09782-0
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 2012330-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Origins Space Telescope: baseline mission concept
    SPIE-Intl Soc Optical Eng ; 2021
    In:  Journal of Astronomical Telescopes, Instruments, and Systems Vol. 7, No. 01 ( 2021-1-6)
    Details
    In: Journal of Astronomical Telescopes, Instruments, and Systems, SPIE-Intl Soc Optical Eng, Vol. 7, No. 01 ( 2021-1-6)
    Type of Medium: Online Resource
    ISSN: 2329-4124
    URL: Article
    DOI: 10.1117/1.JATIS.7.1.011002
    Language: Unknown
    Publisher: SPIE-Intl Soc Optical Eng
    Publication Date: 2021
    detail.hit.zdb_id: 2799363-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Preparing for LSST data : Estimating the physical properties of z 〈 2.5 main-sequence galaxies
    EDP Sciences ; 2021
    In:  Astronomy & Astrophysics Vol. 653 ( 2021-09), p. A107-
    Details
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 653 ( 2021-09), p. A107-
    Abstract: Aims. We study how the upcoming Legacy Survey of Space and Time (LSST) data from the Vera C. Rubin Observatory can be employed to constrain the physical properties of normal star-forming galaxies (main-sequence galaxies). Because the majority of the observed LSST objects will have no auxiliary data, we use simulated LSST data and existing real observations to test the reliability of estimates of the physical properties of galaxies, such as their star formation rate (SFR), stellar mass ( M star ), and dust luminosity ( L dust ). We focus on normal star-forming galaxies because they form the majority of the galaxy population in the universe and are therefore more likely to be observed with the LSST. Methods. We performed a simulation of LSST observations and uncertainties of 50 385 real galaxies within the redshift range 0  〈   z   〈  2.5. In order to achieve this goal, we used the unique multi-wavelength data from the Herschel Extragalactic Legacy Project (HELP) survey. Our analysis focused on two fields, ELAIS N1 and COSMOS. To obtain the physical properties of the galaxies, we fit their spectral energy distributions (SEDs) using the Code Investigating GALaxy Emission. We simulated the LSST data by convolving the SEDs fitted by employing the multi-wavelength observations. We compared the main galaxy physical properties, such as SFR, M star , and L dust obtained from the fit of the observed multi-wavelength photometry of galaxies (from the UV to the far-IR) to those obtained from the simulated LSST optical measurements alone. Results. We present the catalogue of simulated LSST observations for 23 291 main-sequence galaxies in the ELAIS N1 field and for 9093 galaxies in the COSMOS field. It is available in the HELP virtual observatory. The stellar masses estimated based on the LSST measurements agree with the full UV to far-IR SED estimates because they mainly depend on the UV and optical emission, which is well covered by LSST in the considered redshift range. Instead, we obtain a clear overestimate of the dust-related properties (SFR, L dust , M star ) estimated with the LSST alone. They are highly correlated with redshift. We investigate the cause of this overestimate and conclude that it is related to an overestimate of the dust attenuation in both UV and near-IR. We find that it is necessary to employ auxiliary rest-frame mid-IR observations, simulated UV observations, or the far-UV attenuation (AFUV)- M star relation to correct for the overestimate. We also deliver the correction formula log 10 (SFR LSST /SFR real ) = 0.26 ⋅  z 2  − 0.94 ⋅  z  + 0.87. It is based on the 32 384 MS galaxies detected with Herschel .
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    URL: Article
    DOI: 10.1051/0004-6361/202140854
    RVK:
    UA 1000
    RVK:
    US 1090
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2021
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Unsupervised classification of CIGALE galaxy spectra
    EDP Sciences ; 2022
    In:  Astronomy & Astrophysics Vol. 663 ( 2022-07), p. A21-
    Details
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 663 ( 2022-07), p. A21-
    Abstract: Aims. Our study aims at providing deeper insight into the power and limitation of an unsupervised classification algorithm (called Fisher-EM) on spectra of galaxies. This algorithm uses a Gaussian mixture in a discriminative latent subspace. To this end, we investigate the capacity of this algorithm to segregate the physical parameters used to generate mock spectra and the influence of the noise on the classification. Methods. With the code CIGALE and different values for nine input parameters characterising the stellar population, we simulated a sample of 11 475 optical spectra of galaxies containing 496 monochromatic fluxes. The statistical model and the optimum number of clusters are given in Fisher-EM by the integrated completed likelihood (ICL) criterion. We repeated the analyses several times to assess the robustness of the results. Results. Two distinct classifications can be distinguished in the case of the noiseless spectra. The classification with more than 13 clusters disappears when noise is added, while the classification with 12 clusters is very robust against noise down to a signal-to-noise ratio (S/N) of 3. At S / N  = 1, the optimum is 5 clusters, but the classification is still compatible with the previous classification. The distribution of the parameters used for the simulation shows an excellent discrimination between classes. A higher dispersion both in the spectra within each class and in the parameter distribution leads us to conclude that despite a much higher ICL, the classification with more than 13 clusters in the noiseless case is not physically relevant. Conclusions. This study yields two conclusions that are valid at least for the Fisher-EM algorithm. Firstly, the unsupervised classification of spectra of galaxies is both reliable and robust to noise. Secondly, such analyses are able to extract the useful physical information contained in the spectra and to build highly meaningful classifications. In an epoch of data-driven astrophysics, it is important to trust unsupervised machine-learning approaches that do not require training samples that are unavoidably biased.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    URL: Article
    DOI: 10.1051/0004-6361/202141729
    RVK:
    UA 1000
    RVK:
    US 1090
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2022
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Dusty Starbursts Masquerading as Ultra-high Redshift Galaxies in JWST CEERS Observations
    American Astronomical Society ; 2023
    In:  The Astrophysical Journal Letters Vol. 943, No. 2 ( 2023-02-01), p. L9-
    Details
    In: The Astrophysical Journal Letters, American Astronomical Society, Vol. 943, No. 2 ( 2023-02-01), p. L9-
    Abstract: Lyman-break galaxy (LBG) candidates at z ≳ 10 are rapidly being identified in James Webb Space Telescope (JWST)/NIRCam observations. Due to the (redshifted) break produced by neutral hydrogen absorption of rest-frame UV photons, these sources are expected to drop out in the bluer filters while being well detected in redder filters. However, here we show that dust-enshrouded star-forming galaxies at lower redshifts ( z ≲ 7) may also mimic the near-infrared (near-IR) colors of z 〉 10 LBGs, representing potential contaminants in LBG candidate samples. First, we analyze CEERS-DSFG-1, a NIRCam dropout undetected in the F115W and F150W filters but detected at longer wavelengths. Combining the JWST data with (sub)millimeter constraints, including deep NOEMA interferometric observations, we show that this source is a dusty star-forming galaxy (DSFG) at z ≈ 5.1. We also present a tentative 2.6 σ SCUBA-2 detection at 850 μ m around a recently identified z ≈ 16 LBG candidate in the same field and show that, if the emission is real and associated with this candidate, the available photometry is consistent with a z ∼ 5 dusty galaxy with strong nebular emission lines despite its blue near-IR colors. Further observations on this candidate are imperative to mitigate the low confidence of this tentative submillimeter emission and its positional uncertainty. Our analysis shows that robust (sub)millimeter detections of NIRCam dropout galaxies likely imply z ∼ 4–6 redshift solutions, where the observed near-IR break would be the result of a strong rest-frame optical Balmer break combined with high dust attenuation and strong nebular line emission, rather than the rest-frame UV Lyman break. This provides evidence that DSFGs may contaminate searches for ultra-high redshift LBG candidates from JWST observations.
    Type of Medium: Online Resource
    ISSN: 2041-8205 , 2041-8213
    URL: Article
    DOI: 10.3847/2041-8213/acacfe
    Language: Unknown
    Publisher: American Astronomical Society
    Publication Date: 2023
    detail.hit.zdb_id: 2207648-7
    detail.hit.zdb_id: 2006858-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    A hyper luminous starburst at z = 4.72 magnified by a lensing galaxy pair at z = 1.48
    EDP Sciences ; 2020
    In:  Astronomy & Astrophysics Vol. 635 ( 2020-03), p. A27-
    Details
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 635 ( 2020-03), p. A27-
    Abstract: We serendipitously discovered in the Herschel Reference Survey an extremely bright infrared source with S 500  ∼ 120 mJy in the line of sight of the Virgo cluster which we name Red Virgo 4 (RV4). Based on IRAM/EMIR and IRAM/NOEMA detections of the CO(5−4), CO(4−3), and [CI] lines, RV4 is located at a redshift of 4.724, yielding a total observed infrared luminosity of 1.1 ± 0.6 × 10 14 L ⊙ . At the position of the Herschel emission, three blobs are detected with the VLA at 10 cm. The CO(5−4) line detection of each blob confirms that they are at the same redshift with the same line width, indicating that they are multiple images of the same source. In Spitzer and deep optical observations, two sources, High- z Lens 1 (HL1) West and HL1 East, are detected at the center of the three VLA/NOEMA blobs. These two sources are placed at z  = 1.48 with X-shooter spectra, suggesting that they could be merging and gravitationally lensing the emission of RV4. HL1 is the second most distant lens known to date in strong lensing systems. Constrained by the position of the three VLA/NOEMA blobs, the Einstein radius of the lensing system is 2.2″ ± 0.2 (20 kpc). The high redshift of HL1 and the large Einstein radius are highly unusual for a strong lensing system. In this paper, we present the insterstellar medium properties of the background source RV4. Different estimates of the gas depletion time yield low values suggesting that RV4 is a starburst galaxy. Among all high- z submillimeter galaxies, this source exhibits one of the lowest L [CI] to L IR ratios, 3.2 ± 0.9 × 10 −6 , suggesting an extremely short gas depletion time of only 14 ± 5 Myr. It also shows a relatively high L [CI] to L CO(4−3) ratio (0.7 ± 0.2) and low L CO(5−4) to L IR ratio (only ∼50% of the value expected for normal galaxies) hinting at low density of gas. Finally, we discuss the short depletion time of RV4. It can be explained by either a very high star formation efficiency, which is difficult to reconcile with major mergers simulations of high- z galaxies, or a rapid decrease of star formation, which would bias the estimate of the depletion time toward an artificially low value.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    URL: Article
    DOI: 10.1051/0004-6361/201936727
    RVK:
    UA 1000
    RVK:
    US 1090
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2020
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    A Long Time Ago in a Galaxy Far, Far Away: A Candidate z ∼ 12 Galaxy in Early JWST CEERS Imaging
    American Astronomical Society ; 2022
    In:  The Astrophysical Journal Letters Vol. 940, No. 2 ( 2022-12-01), p. L55-
    Details
    In: The Astrophysical Journal Letters, American Astronomical Society, Vol. 940, No. 2 ( 2022-12-01), p. L55-
    Abstract: We report the discovery of a candidate galaxy with a photo- z of z ∼ 12 in the first epoch of the James Webb Space Telescope (JWST) Cosmic Evolution Early Release Science Survey. Following conservative selection criteria, we identify a source with a robust z phot = 11.8 − 0.2 + 0.3 (1 σ uncertainty) with m F200W = 27.3 and ≳7 σ detections in five filters. The source is not detected at λ 〈 1.4 μ m in deep imaging from both Hubble Space Telescope (HST) and JWST and has faint ∼3 σ detections in JWST F150W and HST F160W, which signal a Ly α break near the red edge of both filters, implying z ∼ 12. This object (Maisie’s Galaxy) exhibits F115W − F200W 〉 1.9 mag (2 σ lower limit) with a blue continuum slope, resulting in 99.6% of the photo- z probability distribution function favoring z 〉 11. All data-quality images show no artifacts at the candidate’s position, and independent analyses consistently find a strong preference for z 〉 11. Its colors are inconsistent with Galactic stars, and it is resolved ( r h = 340 ± 14 pc). Maisie’s Galaxy has log M * / M ⊙ ∼ 8.5 and is highly star-forming (log sSFR ∼ −8.2 yr −1 ), with a blue rest-UV color ( β ∼ −2.5) indicating little dust, though not extremely low metallicity. While the presence of this source is in tension with most predictions, it agrees with empirical extrapolations assuming UV luminosity functions that smoothly decline with increasing redshift. Should follow-up spectroscopy validate this redshift, our universe was already aglow with galaxies less than 400 Myr after the Big Bang.
    Type of Medium: Online Resource
    ISSN: 2041-8205 , 2041-8213
    URL: Article
    DOI: 10.3847/2041-8213/ac966e
    Language: Unknown
    Publisher: American Astronomical Society
    Publication Date: 2022
    detail.hit.zdb_id: 2207648-7
    detail.hit.zdb_id: 2006858-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...