PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Parsing photons in the infrared, UCI-led astronomers uncover signs of earliest galaxies

Hubble Space Telescope data, new statistical method instrumental to research project

2015-09-09
(Press-News.org) Irvine, Calif., Sept. 7, 2015 - Astronomers from the University of California, Irvine and Baltimore's Space Telescope Science Institute have generated the most accurate statistical description yet of faint, early galaxies as they existed in the universe 500 million years after the Big Bang.

In a research paper published today in Nature Communications, the team describes its use of a new statistical method to analyze Hubble Space Telescope data captured during lengthy sky surveys. The method enabled the scientists to parse out signals from the noise in Hubble's deep-sky images, providing the first estimate of the number of small, primordial galaxies in the early universe. The researchers concluded that there are close to 10 times more of these galaxies than were previously detected in deep Hubble surveys.

UCI Ph.D. student Ketron Mitchell-Wynne, lead author on the paper, said the time period under investigation is known as the "epoch of reionization." Coming after the Big Bang and a few hundred million years in which a dark universe was dominated by photon-absorbing neutral hydrogen, the epoch of reionization was characterized by a phase transition of hydrogen gas due to the accelerated process of star and galaxy formation.

"It's the furthest back you can study with the Hubble Space Telescope," Mitchell-Wynne said. Hubble's cameras utilize charge-coupled devices, high-quality electronic image sensors first used in astronomy that later were employed in professional video cameras. The team looked at data spanning optical and infrared wavelengths. Photons in the infrared spectrum come directly from stars and galaxies.

UCI cosmologist Asantha Cooray, research project lead, pointed to recent probes into extragalactic infrared background light by the California Institute of Technology's CIBER instrument. "CIBER measured the infrared background at two wavelengths, 1.1 and 1.6 microns," he said. These measurements led the CIBER group to confirm the existence of "intrahalo light" from stars distributed outside galaxies.

Cooray, professor of physics & astronomy, said: "We believe it's true that there is intrahalo light, but we made a new discovery by looking at five infrared bands with Hubble. We sort of overlap with CIBER and then go into short optical wavelengths, and we see in addition to intrahalo light a new component - stars and galaxies that formed first in the universe."

The deep-sky survey was part of a larger Hubble-based research project called the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey. "CANDELS was not initiated for this cause, but it turns out that the way the data were taken was favorable for what we wanted to do," Mitchell-Wynne said. "From the CIBER analysis, we knew there would be a detection of intrahalo light in the infrared bands. We didn't really know what to expect in the optical ones. With Hubble data, we saw a large drop in the amplitude of the signal between the two. With that spectra, we started to get a little more confident that we were seeing the earliest galaxies."

"For this research, we had to look closely at what we call 'empty pixels,' the pixels between galaxies and stars," Cooray said. "We can separate noise from the faint signal associated with first galaxies by looking at the variations in the intensity from one pixel to another. We pick out a statistical signal that says there is a population of faint objects. We do not see that signal in the optical [wavelengths], only in infrared. This is confirmation that the signal is from early times in the universe."

He thinks these primordial galaxies were very different from the well-defined spiral and disc-shaped galaxies currently visible in the universe. They were more diffuse and populated by giant stars. Cooray noted that more observational proof for his team's findings will be possible with the launch of the James Webb Space Telescope in 2018. "These galaxies are very faint," he said, "so if we have a bigger telescope, like James Webb, we'll be able to go very deep and see them individually."

"This is a very exciting finding," said Henry C. Ferguson, an astronomer at Baltimore's Space Telescope Science Institute and co-principal investigator for CANDELS. "It's the first time that we've been able to convincingly measure this subtle signature of early galaxies with Hubble, giving us a firmer handle on what to look for when the James Webb Space Telescope launches a few years from now."

Another area of research Cooray hopes to pursue in the near future is investigating the same part of the sky in other bands, such as X-rays, using NASA's Chandra X-ray Observatory. "Could there be X-ray emissions associated with this primordial stuff?" he said. "Theoretical astrophysicists have explained that the earliest stars collapsed really quickly because they were so massive. They didn't go supernovae and disperse material; they're actually believed to have collapsed into black holes. We would like to see if there are any X-ray emissions associated with such events."

INFORMATION:

About the University of California, Irvine: Currently celebrating its 50th anniversary, UCI is the youngest member of the prestigious Association of American Universities. The campus has produced three Nobel laureates and is known for its academic achievement, premier research, innovation and anteater mascot. Led by Chancellor Howard Gillman, UCI has more than 30,000 students and offers 192 degree programs. It's located in one of the world's safest and most economically vibrant communities and is Orange County's second-largest employer, contributing $4.8 billion annually to the local economy. For more on UCI, visit http://www.uci.edu.

Media access: Radio programs/stations may, for a fee, use an on-campus ISDN line to interview UC Irvine faculty and experts, subject to availability and university approval. For more UC Irvine news, visit news.uci.edu. Additional resources for journalists may be found at communications.uci.edu/for-journalists.



ELSE PRESS RELEASES FROM THIS DATE:

24-hour OBs, midwives lead to less C-sections

2015-09-09
Privately insured pregnant women are less likely to have C-sections when their regular care includes midwives and 24-hour obstetrician coverage, according to a study by researchers at UC San Francisco and Marin General Hospital. The study published online in Obstetrics & Gynecology, on Sept. 8, compared the number of C-sections among women with private insurance, before and after an overhaul of staff practices at Marin General Hospital. Prior to April 2011, private patients at this community hospital in Northern California were managed under a conventional model, in ...

Mothers use variety of strategies to mitigate risks to daughters' body image -- Ben-Gurion University

2015-09-09
BEER-SHEVA, Israel...September 9, 2015 -- Ben-Gurion University of the Negev (BGU) research demonstrates how Jewish mothers' emphasis on the many aspects of well being, fitness and a sense of self-fulfillment helps to counteract the innumerable "ideal" body images seen and heard by their daughters in the mass media. The new study published in Feminism and Psychology focuses on how Jewish mothers instilled resilience in their daughters to combat body dissatisfaction, which can lead to eating disorders. It included 20 pairs of mothers and adult-age daughters and eight other ...

Making IoT configuration more secure and easy to use

2015-09-09
With an ever increasing number of everyday objects from our homes, workplaces and even from our wardrobes, getting connected to the Internet, known as the 'Internet of Things (IoT), researchers from the University of Southampton have identified easy-to-use techniques to configure IoT objects, to make them more secure and hence help protect them from online attacks. This increased connectivity brings additional risk. Setting personalised and strong passwords when connecting new devices to the Internet, for example through our home Wi-Fi networks, can mitigate such risks. ...

Effects of MVA85A vaccine on tuberculosis

2015-09-09
Liverpool, 9 September 2015 - A new systematic review of animal studies testing a vaccine for tuberculosis raises questions about whether the studies provided sufficient evidence to move into trials of children. The new vaccine was a virus-expressing antigen 85A (MVA85A) designed to boost the immunity offered by the existing Bacillus Calmette-Guérin (BCG) vaccine which has little protective effect in practice. The review, published today in the International Journal Epidemiology, evaluates the animal evidence that contributed to the decision to conduct human studies. ...

Fighting customs fraud: JRC research leads to new legislation

2015-09-09
A new regulation adopted by the European Parliament and the Council will allow customs to access information to track the origins and routes of cargo containers arriving in the EU. This new capability will support the fight against customs fraud both at EU and national level. The JRC has been instrumental in the conception and adoption of this legislation by providing the scientific evidence on the importance of analysing electronic records on cargo container traffic. The EU customs authorities have been long aware that information on the logistics and actual routes of ...

Preventing chromosomal chaos: Protein-based genome-stabilizing mechanism discovered

2015-09-09
Most people are familiar with the double-helix shape that allows genetic information to be packed into a molecule of human DNA. Less well-known is how all this information - which, if laid end-to-end, would stretch some three meters - is packed into the cellular nucleus. The secret of how this crush of genetic code avoids chaos - remaining untangled, correctly compartmentalized, and available for accurate DNA replication - has recently been revealed. By tracking and analyzing the movement of fluorescently-tagged genomic regions within the nuclei of live cells, an international ...

Epicolactones -- the 8-step path

2015-09-09
In the latest issue of the journal Nature Chemistry researchers led by Dirk Trauner, Professor of Chemical Biology and Genetics at LMU Munich, describe the biomimetic synthesis of epicolactone, a compound which was first isolated from an endophytic fungus. "What we have accomplished is one of the shortest and most elegant total syntheses of a natural product ever reported," says Trauner, as he and his colleagues have indeed succeeded in producing a highly complex molecular structure in a minimal number of steps. "This is actually very close to being an ideal synthesis - ...

Capturing introns: Targeting rapidly evolving regions of the genome for phylogenetics

2015-09-09
Understanding the evolutionary history of organisms is important for myriad reasons. To name a few, information about relationships between species can be used to guide the classification of biodiversity, inform conservation policies aimed at protecting threatened species, aid in tracking the spread of pathogens, and can even play a role in the discovery of new medicines. Scientists depict the relationships between species with evolutionary trees, also called phylogenies. A phylogeny shows the accumulation of species through time and the relationships between these species, ...

Study points to a possible new pathway toward a vaccine against MRSA

2015-09-09
New research led by NYU Langone Medical Center has uncovered why a particular strain of Staphylococcus aureus -- known as HA-MRSA -- becomes more deadly than other variations. These new findings open up possible new pathways to vaccine development against this bacterium, which the Centers for Disease Control and Preventions says accounts for over 10,000 deaths annually, mostly among hospital patients. In a series of experiments in mice and in human immune cells in the lab, recently published in the journal Nature Communications online Sept. 2, the NYU Langone team found ...

Nearly half of testicular cancer risk comes from inherited genetic faults

2015-09-09
Almost half of the risk of developing testicular cancer comes from the DNA passed down from our parents, a new study reports. The research suggests genetic inheritance is much more important in testicular cancer than in most other cancer types, where genetics typically accounts for less than 20 per cent of risk. The findings suggest testing for a range of genetic variants linked to testicular cancer could be effective in picking out patients who are at substantially increased risk - potentially opening up ways of preventing the disease. Scientists at The Institute ...

LAST 30 PRESS RELEASES:

IOP Publishing and IPEM mandate reporting of sex and gender in research 

Dogs trained to detect trauma stress by smelling humans’ breath

Electronic device thermal management made simpler and slightly better!

Study: Dangerous surgical site infections can be reduced with simple prevention protocol

Genetic testing of patients with atrial fibrillation can alert clinicians to potential development of life-threatening conditions

Artificial Intelligence tool successfully predicts fatal heart rhythm

What progress has China made in agriculture green development over the past five years?

ALMA finds new molecular signposts in starburst galaxy

Open waste burning linked to air pollution in Northwestern Greenland

Google Street View reveals how built environment correlates with risk of cardiovascular disease

Connecting the dots to shape growth forces

Parental avoidance of toxic exposures could help prevent autism, ADHD in children, new study shows

Trends in the incidence of renal replacement therapy due to rapidly progressive glomerulonephritis in Japan, 2006–2021

Olympics not likely to swallow up skateboarding’s subversive nature into its corporate spectacle, study says

Looking after the NHS workforce must be a top priority, say experts

Prolonged use of certain hormone drugs linked to increased brain tumor risk

Delirium a ‘strong risk factor’ for dementia among older people

People experiencing homelessness more likely to develop dementia at younger ages, study finds

Can metalens be commercialized at a fraction of the cost?

Reclaim ‘wellness’ from the rich and famous, and restore its political radicalism, new book argues

Curtin research unlocks supernova stardust secrets

New documents reveal patient safety concerns over strike day cover

UTA hosts Solar-bration watch party for April 8 eclipse

Researchers discover molecule that promotes production of cancer cells in triple-negative breast cancer

New tool provides researchers with improved understanding of stem cell aging in the brain

Around half of people living with HIV in developed countries are now aged 50 years and over and at higher risk of becoming frail and having multiple comorbidities

You are never too old for an STI – more older adults being diagnosed with STIs such as gonorrhea and syphilis

University of Minnesota researchers introduce enhanced brain signal analysis technique

Aston University research center to focus on using AI to improve lives

Robot, can you say ‘cheese’?

[Press-News.org] Parsing photons in the infrared, UCI-led astronomers uncover signs of earliest galaxies
Hubble Space Telescope data, new statistical method instrumental to research project