Luminous galaxy reionizing surroundings 13 billion years ago

Agencies
July 2, 2020

Leiden, Jul 2: Astronomers have discovered a luminous galaxy caught in the act of reionizing its surrounding gas only 800 million years after the Big Bang.

The research, led by Romain Meyer, PhD student at UCL in London, UK, has been presented at the virtual annual meeting of the European Astronomical Society (EAS).

Studying the first galaxies that formed 13 billion years ago is essential to understanding our cosmic origins. One of the current hot topics in extragalactic astronomy is 'cosmic reionization,' the process in which the intergalactic gas was ionized (atoms stripped of their electrons).

Cosmic reionization is similar to an unsolved murder: We have clear evidence for it, but who did it, how and when? We now have strong evidence that hydrogen reionization was completed about 13 billion years ago, in the first billion years of the universe, with bubbles of ionized gas slowly growing and overlapping.

The objects capable of creating such ionized hydrogen bubbles have however remained mysterious until now: the discovery of a luminous galaxy in which 60-100 percent of ionizing photons escape, is likely responsible for ionizing its local bubble. This suggests the case is closer to being solved.

The two main suspects for cosmic reionization are usually 1) a population of numerous faint galaxies leaking ~10 percent of their energetic photons, and 2) an 'oligarchy' of luminous galaxies with a much larger percentage (>50 percent) of photons escaping each galaxy.

In either case, these first galaxies were very different from those today: galaxies in the local universe are very inefficient leakers, with only <2-3 percent of ionizing photons escaping their host. To understand which galaxies governed cosmic reionization, astronomers must measure the so-called escape fractions of galaxies in the reionization era.

The detection of light from excited hydrogen atoms (the so-called Lyman-alpha line) can be used to infer the fraction of escaping photons. On the one hand, such detections are rare because reionization-era galaxies are surrounded by neutral gas which absorbs that signature hydrogen emission.

On the other hand, if this hydrogen signal is detected it represents a 'smoking gun' for a large ionized bubble, meaning we have caught a galaxy reionizing its surroundings. The size of the bubble and the galaxy's luminosity determines whether it is solely responsible for creating this ionized bubble or if unseen accomplices are necessary.

The discovery of a luminous galaxy 800 million years after the Big Bang supports the scenario where an 'oligarchy' of bright leakers emits most of the ionizing photons.

"It is the first time we can point to an object responsible for creating an ionized bubble, without the need for a contribution from unseen galaxies.

Additional observations with the upcoming James Webb Space Telescope will enable us to study further what is likely one of the best suspects for the unsolved case of cosmic reionization," said Meyer.

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News Network
March 13,2020

Bengaluru, Mar 13: In the wake of fresh cases of Covid-19 reported in Karnataka, Infosys Foundation chairperson Sudha Murty has urged the Karnataka government to take steps to shut malls and theatres, saying the coronavirus multiplies in air-conditioned areas.

In a letter to the government, she said preventive measures should be taken to control the spread of coronovirus before it gets worse.

Murty, who also leads the State government-constituted Karnataka Tourism Task Force, said she has discussed the current situation with Chairman and Executive Director of Narayana Health, Devi Prasad Shetty.

She suggested closure of all schools and colleges with immediate effect, malls, theatres and “all air-conditioned areas where the virus multiplies”, and allow only essential services like pharmacy, grocery and petrol bunks.

“It is not scientifically proven that the virus dies in high temperature,” she said pointing to spread of the virus -- despite heat -- in peak summer in Australia and Singapore, which have “summer all 12 months”.

“I request you to vacate one government hospital with at least 500 - 700 beds for this purpose (to deal with coronavirus cases), which requires oxygen lines and pipes,” she said.

“Infosys Foundation, the philanthropic and CSR arm of software major Infosys, would do the civil work and Devi Shetty has agreed to share resources like medical equipment,” she added.

“We would like to work with the government proactively so that we can prevent this as early as possible,” Sudha Murty said.

The total number of confirmed coronavirus positive cases in Karnataka is five, including the 76-year old man from Kalaburagi who died on Tuesday night.

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Agencies
July 6,2020

The Covid-19 pandemic has made an unprecedented impact on the Indian businesses, particularly small and medium enterprises (SMEs) and startups. According to a joint survey by FICCI and Indian Angel Network (IAN), the pandemic has hit the businesses of around 70% startups.

With uncertainty in the business environment and an unexpected shift in priorities of the government as well as corporates, many startups are struggling to survive, it says.

In a nationwide survey on the 'Impact of Covid-19 on Indian Startups' involving 250 startups, 70% participants said their businesses had been impacted by Covid-19 and around 12% had shut operations.

The survey shows only 22% startups have cash reserves to meet the fixed cost expenses over the next 3-6 months, and 68% are reducing operational and administrative expenses.

Around 30% of the companies said they would retrench employees if the lockdown was extended too long. The 43% startups have already started 20-40% salary cuts over April-June.

Over 33% startups said investors had put the investment decision on hold and 10% said the deals had been scrapped. Only 8% startups had received funds as per the deals signed before Covid-19 outbreak, the survey revealed.

The reduced funding has forced startups to put a hold on business development and manufacturing activities, which has resulted in loss of projected orders.

The survey highlights the need of an urgent relief package for startups, including possible purchase orders from the government, tax relief and swifter tax refunds, and immediate fiscal support measures, including grants, soft loans and payroll grants.

Besides 250 startups, 61 incubators and investors also participated in the survey.

While 96% of investors accepted that their investments in startups had been impacted by Covid-19, 92% said their investments in startups would continue to be low over the next six months.

Around 59% investors said they would prefer to work with the existing portfolio firms in the coming months. Only 41% said they would consider new deals.

"A comparison of priority investment sectors before and during Covid-19 shows 35% investors are now looking at investments in healthcare startups, followed by EdTech, AI/Deep Tech, FinTech and Agri," said the survey.

Around 44% incubators surveyed said their day-to-day operations had been considerably hit by Covid-19. Most incubators are now supporting their portfolio firms by providing them virtual platforms to interact with mentors, investors and industries.

Dilip Chenoy, FICCI Secretary General, said, "The startup sector is stressed for survival at the moment. The investment sentiment is also subdued and is expected to remain so in the coming months. Lack of working capital and cash flows may lead to major layoffs over the next 3-6 months."

Indian startups needed an enabling ecosystem and flow of funds to continue operations, the survey said.

Padmaja Ruparel, President, Indian Angel Network & Co-Chair of FICCI Startup Committee, said, "In these uncertain times, as investors, we must play an important role to provide the Indian startups funding, mentoring and hand-holding support to stay afloat and come out at the other end of this crisis."

To that end, IAN recently announced a debt fund to help IAN portfolio companies raise working capital and ensure business continuity by partnering with debt providers.

This must be replicated on a wider scale, so a larger number of startups are provided the capital support to make it during these tough times, Ruparel said.

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Agencies
January 12,2020

Washington D.C., Jan 12: A recent study has claimed that people end up wasting almost an entire day when they take a vacation.

This can happen while standing in a queue or searching for places to visit, people do not keep a count of the time they have actually utilised during the trip. As a result, they end up doing much lesser activities than they originally had planned.

According to a recent report in Fox News, the study has also shared the fact that people try to justify time waste with planning and scheduling activities whereas the truth is that these things can be done well ahead to save time during the trip.

The average time waste according to the study commissioned by Sykes Holiday Cottages also said the people taking a seven days' trip waste a minimum of 17-and-a-half hours to figure out various factors.

But there are other causes involved as well. When one visits any crowded location, the real-time spent to enjoy the location is lesser than the time spent on reaching and trying to get involved. For instance, if one visits an amusement park, the activities take lesser time than the preparatory and other phases.

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