scholarly journals Unveiling the most luminous Lyman-α emitters in the epoch of reionisation

2019 ◽  
Vol 15 (S352) ◽  
pp. 21-25
Author(s):  
Jorryt Matthee ◽  
David Sobral
Keyword(s):  
Interstellar Medium ◽  
Complex Systems ◽  
Rest Frame ◽  
Big Bang ◽  
Young Stars ◽  
Spatially Resolved ◽  
Luminous Galaxies ◽  
Follow Up Studies ◽  
The Big Bang

AbstractDistant luminous Lyman-α emitters are excellent targets for detailed observations of galaxies in the epoch of reionisation. Spatially resolved observations of these galaxies allow us to simultaneously probe the emission from young stars, partially ionised gas in the interstellar medium and to constrain the properties of the surrounding hydrogen in the circumgalactic medium. We review recent results from (spectroscopic) follow-up studies of the rest-frame UV, Lyman-α and [CII] emission in luminous galaxies observed ∼500 Myr after the Big Bang with ALMA, HST/WFC3 and VLT/X-SHOOTER. These galaxies likely reside in early ionised bubbles and are complex systems, consisting of multiple well separated and resolved components where traces of metals are already present.

scholarly journals Probing the circumstellar medium 2.8 Gyr after the big bang: detection of Bowen fluorescence in the Sunburst arc

2020 ◽  
Vol 499 (1) ◽  
pp. L67-L71
Author(s):  
E Vanzella ◽  
M Meneghetti ◽  
A Pastorello ◽  
F Calura ◽  
E Sani ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Rest Frame ◽  
Angular Resolution ◽  
Big Bang ◽  
High Angular Resolution ◽  
Physical Origin ◽  
Transient Event ◽  
Eta Carinae ◽  
Transient Events ◽  
The Big Bang

ABSTRACT We discovered Bowen emission arising from a strongly lensed (i.e. with magnification factor μ > 20) source hosted in the Sunburst arc at z = 2.37. We claim this source is plausibly a transient stellar object and study the unique ultraviolet lines emerging from it. In particular, narrow (σv ≃ 40 km s−1) ionization lines of Fe fluoresce after being exposed to Ly α (1216 Å) radiation that pumps selectively their atomic levels. Data from VLT/MUSE, X-Shooter, and ESPRESSO observations (the latter placed at the focus of the four UTs) at increasing spectral resolution of R = 2500, 11 400, and 70 000, respectively, confirm such fluorescent lines are present since at least 3.3 yr (≃1 yr rest frame). Additional Fe forbidden lines have been detected, while C and Si doublets probe an electron density ne ≳ 106 cm−3. Similarities with the spectral features observed in the circumstellar Weigelt blobs of Eta Carinae probing the circumstellar dense gas condensations in radiation-rich conditions are observed. We discuss the physical origin of the transient event, which remains unclear. We expect such transient events (including also supernova or impostors) will be easily recognized with ELTs thanks to high angular resolution provided by adaptive optics and large collecting area, especially in modest (μ < 3) magnification regime.

scholarly journals GRB 130606A AS A PROBE OF THE INTERGALACTIC MEDIUM AND THE INTERSTELLAR MEDIUM IN A STAR-FORMING GALAXY IN THE FIRST Gyr AFTER THE BIG BANG

2013 ◽  
Vol 774 (1) ◽  
pp. 26 ◽  
Author(s):  
Ryan Chornock ◽  
Edo Berger ◽  
Derek B. Fox ◽  
Ragnhild Lunnan ◽  
Maria R. Drout ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Intergalactic Medium ◽  
Big Bang ◽  
Star Forming ◽  
The Big Bang

scholarly journals The Pristine survey XI: the FORS2 sample

2020 ◽  
Vol 493 (4) ◽  
pp. 4677-4691 ◽  
Author(s):  
E Caffau ◽  
P Bonifacio ◽  
L Sbordone ◽  
A M Matas Pinto ◽  
P François ◽  
...  
Keyword(s):  
Narrow Band ◽  
Broad Band ◽  
Wide Band ◽  
Big Bang ◽  
Wide Field ◽  
Low Resolution ◽  
Giant Stars ◽  
Carbon Abundance ◽  
The Big Bang

Abstract Extremely metal-poor (EMP) stars are old objects that mostly formed very early after the big bang. They are rare and, to select them, we have to rely on low-resolution spectroscopic or photometric surveys; specifically the combination of narrow- and broad-band photometry provides a powerful and time efficient way to select MP stars. The Pristine photometric survey is using the Canada–France–Hawaii Telescope MegaCam wide-field imager to obtain narrow-band photometry by utilizing a filter centred at 395.2 nm on the Ca ii-H and -K lines. Gaia DR 2 is providing us the wide-band photometry as well as parallaxes. Follow-up observations of MP candidates allowed us to improve our photometric calibrations. In this paper of the series we analyse MP stars observed with FORS2 at VLT. We demonstrate the Pristine calibration adopted in this work to be able to provide metallicities accurate to ±0.3 dex for MP giant stars with good parallaxes, while it performs poorly for dwarf and turn-off stars, whatever the accuracy on the parallaxes. We find some MP and very MP stars that are not enhanced in α elements. Such stars have already been found in several other searches, and a higher resolution follow-up of our sample would be useful to put our findings on a firmer ground. This sample of stars analysed has a low fraction of carbon-enhanced MP stars, regardless of the definition adopted. This deficiency could indicate a small sensitivity of the Pristine filter to carbon abundance, issue to be addressed in the future.

scholarly journals The multiple merger assembly of a hyperluminous obscured quasar at redshift 4.6

Science ◽  
2018 ◽  
Vol 362 (6418) ◽  
pp. 1034-1036 ◽  
Author(s):  
T. Díaz-Santos ◽  
R. J. Assef ◽  
A. W. Blain ◽  
M. Aravena ◽  
D. Stern ◽  
...  
Keyword(s):  
Black Holes ◽  
Far Infrared ◽  
Big Bang ◽  
Galaxy Mergers ◽  
Dynamical Interaction ◽  
Dominant Mechanism ◽  
Luminous Galaxies ◽  
Merger Event ◽  
Gas Accretion ◽  
The Big Bang

Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56−052634.9 (W2246−0526), a dust-obscured quasar at redshift 4.6, 1.3 billion years after the Big Bang. Far-infrared dust continuum observations show three galaxy companions around W2246−0526 with disturbed morphologies, connected by streams of dust likely produced by the dynamical interaction. The detection of tidal dusty bridges shows that W2246−0526 is accreting its neighbors, suggesting that merger activity may be a dominant mechanism through which the most luminous galaxies simultaneously obscure and feed their central supermassive black holes.

scholarly journals Impact of a caries preventive intervention in remote Indigenous Australian children

2019 ◽  
Author(s):  
Ratilal Lalloo ◽  
TADAKAMADLA SANTOSH KUMAR ◽  
Jeroen Kroon ◽  
Lisa M Jamieson ◽  
Newell Johnson
Keyword(s):  
Comparison Group ◽  
Preventive Intervention ◽  
Big Bang ◽  
Carious Lesions ◽  
Caries Increment ◽  
Indigenous Children ◽  
Preventive Fraction ◽  
The Big Bang ◽  
Experimental Group

IMPORTANCE: The burden of dental caries in remote Indigenous communities in Australia is unacceptably high. OBJECTIVES: We tested the impact of an annual caries preventive intervention, delivered by a fly-in/fly-out professional team, on Indigenous children residing in a remote Australian community, involving selective fissure sealants, topical povidone iodine and fluoride varnish application. The outcome was caries increment at 12- and 24-month follow-up. DESIGN, SETTING, PARTICIPANTS: Around 600 Indigenous children aged 5 to 17 years were invited to participate at baseline, of which 408 had caregiver consent provided. Of these, 196 consented to both the study and the treatment arm and comprised the experimental group. Two hundred and twelve consented to the epidemiological examination only, and constituted the comparison group. INTERVENTION: The Big Bang intervention, which occurred annually, comprised placement of fissure sealants, and application of povidone-iodine and fluoride varnish, following completion of each childs dental treatment plan. Standard diet and oral hygiene advice was provided. MAIN OUTCOMES AND MEASURES: Caries increment (number of tooth surfaces with new dental caries) in both primary and permanent dentitions at 12- and 24-month follow-up. RESULTS: At 12-month follow-up, children in the experimental group had, on average, 5.05 (5.47) new carious lesions compared to 7.49 (6.94) in the comparison group (p=0.001). The preventive fraction was 33%. At 24-month follow-up, children in the experimental group had, on average, 6.47 (6.07) new carious lesions compared to 8.43 (5.83) in the comparison group (p=0.002). The preventive fraction was 23%. CONCLUSIONS AND RELEVANCE: Indigenous children exposed to the Big Bang caries intervention had significantly less increment in dental disease than those not exposed to the intervention. Benefits were demonstrated at both 12- and 24-month follow-ups, suggesting that the intervention is likely to be sustained if delivered across a childs life. The cost-effectiveness of this approach is being evaluated.

What graduate follow-up studies can tell us

2000 ◽  
Vol 34 (12) ◽  
pp. 976-977 ◽  
Author(s):  
Linda H Distlehorst
Keyword(s):  
Follow Up Studies

A view of the universe before the big bang

2006 ◽  
Vol 190 ◽  
pp. 15-15
Author(s):  
D CASTELVECCHI
Keyword(s):  
Big Bang ◽  
The Big Bang ◽  
The Universe

Beurteilung der Adriamycin-Kardiotoxizität mittels der Äquilibrium-Radionuklid-Ventrikulographie

1987 ◽  
Vol 26 (05) ◽  
pp. 206-211 ◽  
Author(s):  
P. Knesewitsch ◽  
N. H. Göldel ◽  
S. Fritsch ◽  
E. Moser
Keyword(s):  
Left Ventricular ◽  
Peak Filling Rate ◽  
Base System ◽  
Filling Rate ◽  
Time To Peak ◽  
Ejection Rate ◽  
Follow Up Studies ◽  
Pathologic Findings ◽  
Peak Ejection Rate

Results of 606 equilibrium radionuclide ventriculographies (ERNV) performed in 348 non-selected patients receiving Adriamycin (ADM) therapy were stored in a data base system. The aim of the study was to assess the influence of a potential cardiotoxic therapy on left ventricular pump function. Increasing ADM doses yielded a significant (p <0.05) decrease of the resting ejection fraction (R-gEF), the peak ejection rate and the peak filling rate. Enddiastolic and endsystolic volumes increased significantly. Stroke volume, heart rate and time to peak filling rate did not change significantly. 368 follow-up studies were performed in 128 patients: 65/128 patients presented a decrease of R-gEF, but only in 45 of these patients R-gEF values fell into the pathologic range. In 44 of these follow-ups, R-gEF remained unchanged. In 19 patients, a R-gEF increase was observed. At the beginning of ADM therapy 14% of the patients had subnormal R-gEF values. With increasing ADM doses pathologic findings increased to 86% in patients with ADM doses higher than 500 mg/m2.

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