36 research outputs found
Evolution of the UV LF from z~15 to z~8 Using New JWST NIRCam Medium-Band Observations over the HUDF/XDF
Here we present the first constraints on the prevalence of z>10 galaxies in
the Hubble Ultra Deep Field (HUDF) leveraging new NIRCam medium-band
observations taken with JWST. These NIRCam observations probe redward of
1.6microns, beyond the wavelength limit of HST, allowing us to search for
galaxies to z>10. These observations indicate that the highest redshift
candidate identified over the HUDF with HST, UDFj-39546284, has a redshift of
z=12.0+/-0.1, as had been suggested in multiple analyses of the HUDF12/XDF
data. This source thus appears to be the most distant galaxy discovered by HST
in its more than 30 years of operation. Additionally, we identify nine other
z~8-13 candidate galaxies over the HUDF, two of which are entirely new
discoveries and appear to lie at z~11 and z~12. We use these results to
characterize the evolution of the UV luminosity function (LF) from z~15 to
z~8.7. While our LF results at z~8.7 and z~10.5 are consistent with previous
findings over the HUDF, our new LF estimates at z~12.6 are substantially higher
than other results in the literature, potentially pointing to a milder
evolution in the UV luminosity density from z~12.6. We emphasize that our LF
results are uncertain given the small number of sources in our z~12.6 selection
and limited volume probed. The new NIRCam data also indicate that the faint
z~8-13 galaxies in the HUDF/XDF show very blue UV-continuum slopes beta~-2.7,
high specific star formation rates ~24.5 Gyr, and high EW (~1300A)
[OIII]+Hbeta emission, with two z~8.5 sources showing [OIII]+Hbeta EWs of ~2300
Angstroms.Comment: 19 pages, 14 figures, 7 tables, submitted to MNRAS, with some minor
typos correcte
The JWST FRESCO Survey:Legacy NIRCam/Grism Spectroscopy and Imaging in the two GOODS Fields
We present the JWST cycle 1 53.8 h medium program FRESCO, short for 'First Reionization Epoch Spectroscopically Complete Observations'. FRESCO covers 62 arcmin2 in each of the two GOODS/CANDELS fields for a total area of 124 arcmin2 exploiting JWST's powerful new grism spectroscopic capabilities at near-infrared wavelengths. By obtaining ∼2 h deep NIRCam/grism observations with the F444W filter, FRESCO yields unprecedented spectra at R ∼1600 covering 3.8-5.0 μm for most galaxies in the NIRCam field of view. This setup enables emission line measurements over most of cosmic history, from strong PAH lines at z ∼0.2-0.5, to Pa α and Pa β at z ∼1-3, He i and [S iii] at z ∼2.5-4.5, H α and [N ii] at z ∼5-6.5, up to [O iii] and H β for z ∼7-9 galaxies. FRESCO's grism observations provide total line fluxes for accurately estimating galaxy stellar masses and calibrating slit-loss corrections of NIRSpec/MSA spectra in the same field. Additionally, FRESCO results in a mosaic of F182M, F210M, and F444W imaging in the same fields to a depth of ∼28.2 mag (5σ in 032 diameter apertures). Here, we describe the overall survey design and the key science goals that can be addressed with FRESCO. We also highlight several, early science results, including: spectroscopic redshifts of Lyman break galaxies that were identified almost 20 yr ago, the discovery of broad-line active galactic nuclei at z > 4, and resolved Pa α maps of galaxies at z ∼1.4. These results demonstrate the enormous power for serendipitous discovery of NIRCam/grism observations.</p
The JWST FRESCO Survey: Legacy NIRCam/Grism Spectroscopy and Imaging in the two GOODS Fields
We present the JWST Cycle 1 53.8hr medium program FRESCO, short for "First
Reionization Epoch Spectroscopically Complete Observations". FRESCO covers 62
arcmin in each of the two GOODS/CANDELS fields for a total area of 124
arcmin exploiting JWST's powerful new grism spectroscopic capabilities at
near-infrared wavelengths. By obtaining ~2 hr deep NIRCam/grism observations
with the F444W filter, FRESCO yields unprecedented spectra at R~1600 covering
3.8 to 5.0 m for most galaxies in the NIRCam field-of-view. This setup
enables emission line measurements over most of cosmic history, from strong PAH
lines at z~0.2-0.5, to Pa and Pa at z~1-3, HeI and [SIII] at
z~2.5-4.5, H and [NII] at z~5-6.5, up to [OIII] and H for z~7-9
galaxies, and possibly even [OII] at z~10-12. FRESCO's grism observations
provide total line fluxes for accurately estimating galaxy stellar masses and
calibrating slit-loss corrections of NIRSpec/MSA spectra in the same field.
Additionally, FRESCO results in a mosaic of F182M, F210M, and F444W imaging in
the same fields to a depth of ~28.2 mag (5 in 0.32" diameter
apertures). Together with this publication, the v1 imaging mosaics are released
as high-level science products via MAST. Here, we describe the overall survey
design and the key science goals that can be addressed with FRESCO. We also
highlight several, early science results, including: spectroscopic redshifts of
Lyman break galaxies that were identified almost 20 years ago, the discovery of
broad-line active galactic nuclei at z>4, and resolved Pa maps of
galaxies at z~1.4. These results demonstrate the enormous power for
serendipitous discovery of NIRCam/grism observations. Given the wealth of
ancillary data available in these fields, the zero-proprietary time FRESCO data
is poised to enable a large amount of legacy science by the community.Comment: 11 pages, 11 figures; submitted to MNRAS; for more information on the
survey and data releases, see http://jwst-fresco.astro.unige.ch
The JWST FRESCO Survey: Legacy NIRCam/Grism Spectroscopy and Imaging in the two GOODS Fields
We present the JWST Cycle 1 53.8hr medium program FRESCO, short for “First Reionization Epoch Spectroscopically Complete Observations”. FRESCO covers 62 arcmin2 in each of the two GOODS/CANDELS fields for a total area of 124 arcmin2 exploiting JWST’s powerful new grism spectroscopic capabilities at near-infrared wavelengths. By obtaining ∼2hr deep NIRCam/grism observations with the F444W filter, FRESCO yields unprecedented spectra at R ∼ 1600 covering 3.8 to 5.0 μm for most galaxies in the NIRCam field-of-view. This setup enables emission line measurements over most of cosmic history, from strong PAH lines at z ∼ 0.2 − 0.5, to Paα and Paβ at z ∼ 1 − 3, HeI and [SIII] at z ∼ 2.5 − 4.5, Hα and [NII] at z ∼ 5 − 6.5, up to [OIII] and Hβ for z∼7-9 galaxies. FRESCO’s grism observations provide total line fluxes for accurately estimating galaxy stellar masses and calibrating slit-loss corrections of NIRSpec/MSA spectra in the same field. Additionally, FRESCO results in a mosaic of F182M, F210M, and F444W imaging in the same fields to a depth of ∼28.2 mag (5 σ in 032 diameter apertures). Here, we describe the overall survey design and the key science goals that can be addressed with FRESCO. We also highlight several, early science results, including: spectroscopic redshifts of Lyman break galaxies that were identified almost 20 years ago, the discovery of broad-line active galactic nuclei at z &gt; 4, and resolved Paα maps of galaxies at z ∼ 1.4. These results demonstrate the enormous power for serendipitous discovery of NIRCam/grism observations
The JWST FRESCO survey: legacy NIRCam/grism spectroscopy and imaging in the two GOODS fields
We present the JWST cycle 1 53.8 h medium program FRESCO, short for 'First Reionization Epoch Spectroscopically Complete Observations'. FRESCO covers 62 arcmin2 in each of the two GOODS/CANDELS fields for a total area of 124 arcmin2 exploiting JWST's powerful new grism spectroscopic capabilities at near-infrared wavelengths. By obtaining ∼2 h deep NIRCam/grism observations with the F444W filter, FRESCO yields unprecedented spectra at R ∼1600 covering 3.8-5.0 μm for most galaxies in the NIRCam field of view. This setup enables emission line measurements over most of cosmic history, from strong PAH lines at z ∼0.2-0.5, to Pa α and Pa β at z ∼1-3, He i and [S iii] at z ∼2.5-4.5, H α and [N ii] at z ∼5-6.5, up to [O iii] and H β for z ∼7-9 galaxies. FRESCO's grism observations provide total line fluxes for accurately estimating galaxy stellar masses and calibrating slit-loss corrections of NIRSpec/MSA spectra in the same field. Additionally, FRESCO results in a mosaic of F182M, F210M, and F444W imaging in the same fields to a depth of ∼28.2 mag (5σ in 032 diameter apertures). Here, we describe the overall survey design and the key science goals that can be addressed with FRESCO. We also highlight several, early science results, including: spectroscopic redshifts of Lyman break galaxies that were identified almost 20 yr ago, the discovery of broad-line active galactic nuclei at z > 4, and resolved Pa α maps of galaxies at z ∼1.4. These results demonstrate the enormous power for serendipitous discovery of NIRCam/grism observations
Biocapteur de cyanobactéries potentiellement toxiques pour l'évaluation du risque dans les eaux douces
International audienceHarmful cyanobacterial blooms are a major threat to freshwater ecosystems globally weighing down the Good Environmental Status of waters and risk for human health. Biosensors are a highly promising technology that can produce near real-time measurements that could be used by early warning systems safeguarding human and freshwater ecosystem health. We developed a rapid, sensitive, simple and economical test to identify and daily monitor the blooms of potentially toxic cyanobacteria in aquatic environments based on their genetic identity. This innovative solution comes in a colorimetric biosensor format to quickly and efficiently monitor and sustainably manage the contamination risks of potentially harmful cyanobacteria. The biosensor is a genus-specific ribosomal RNA/DNA probe-based assay of potentially toxic genus and is calibrated to equivalent cell numbers. Here we present the field validation tests results performed in a recreative bathing area in south Paris concerning the detection of Microcystis at different sampling points during summer 2017 campaign. The validation was performed by taxonomic cyanobacteria cell counting present in the samples
State of the art and eVALUE scope
eVALUE will address the real function of ICT-based safety systems and their capability to perform the function through two courses of action: defining and quantifying the function output to be achieved by the safety system and developing the testing and evaluation methods for the ICT-based safety systems. The safety systems within the eVALUE scope are classified into four clusters: longitudinal, lateral and yaw/stability. The fourth cluster remains open for upcoming systems. Based on market availability and penetration rate, the consortium decided to focus on eight preventive or mitigating safety systems: ACC, FCW and CM by braking, in the longitudinal assistance domain; BSD, LDW and LKA, in the lateral assistance domain; and finally, ABS and ESC, in the yaw/stability assistance domain. Following the description of current test and evaluation methods, sensor technologies, system function output and ECUs globally applicable to ICT based safety systems, the report covers these technologies and components for the eight selected systems in detail. As a next step to this deliverable and according to the work plan, concepts for design reviews, physical vehicle testing as well as laboratory testing will be analysed. The result will be an in-depth understanding of the possibilities to investigate and evaluate the eight active safety systems within the first phase of the project. The different concepts will then support the decision about the development of the testing and evaluation methods that are able to point out the safety benefit of those systems in the most representative way