Friday, January 18, 2013

The Endgame Homing in on the Higgs boson

The Higgs boson cannot be seen or detected directly. Being a heavy particle (about 125 times as heavy as a proton), it decays to lighter particles immediately after being created in a collision. Some of these decay products may decay to yet lighter particles. Depending on the final decay products, a number of techniques have been developed to search for the Higgs. There are five important search channels, with the Higgs decaying into:
two photons (diphoton channel),
two Z bosons, each of which decays into two electrons or two muons (4-lepton channel),
two W bosons, each of which decays into an electron or a muon and a corresponding neutrino (lvlv channel),
two tau leptons, which can decay in various ways (tautau channel),
two bottom quarks, with the Higgs being produced in association with a W or a Z boson (bb channel).
Of these, the first two channels are the most sensitive, in that they provide the cleanest signatures of Higgs-like events. In each of these two channels, a number of events were found that looked very Higgs-like.
But when and how was it decided that a particle had been discovered?
In high-energy physics, a specific quantitative measure is used to determine whether or not a discovery has occurred. This is necessary because, for example, events that are not from Higgs boson decays can look like Higgs decays, thus generating a fake Higgs signal. A particular set of events constitutes a discovery when the probability of these events being fakes is less than about 3 parts in 10 million. This is a very small number, and means that the analyzers are highly confident that what they see is a real signal. This probability is interpreted in terms of a significance: the significance necessary to claim a discovery is 5 sigma.
With the data collected by June 2012, ATLAS found that while the diphoton and 4-lepton channels individually had significances of less than 5 sigma, a combination of the two yielded a significance of 5 sigma. At that point, ATLAS was ready to declare a discovery. Meanwhile, the CMS experiment had been analyzing their own data, and they also found that a combination of the diphoton and 4-lepton channels gave 5 sigma significance. So the ATLAS results were independently confirmed. Moreover, the mass of the Higgs boson measured in each of the two channels by each experiment was around 125 GeV, which strengthened our conviction that we are all seeing the same particle. For comparison, the mass of a proton is a little less than a GeV.
The two experiments announced their discoveries in a heavily attended seminar at CERN on the morning of July 4, 2012. I have written about my emotions and experiences on that day previously in a short article, so I will not repeat them, except to say that this was the event of a lifetime in a very true sense.
Progress since the discovery
The Higgs discovery was not the end of the story by any means, since much remained to be done. For a starter, it is not known for certain that the discovered particle is in fact the Higgs boson predicted by the Standard Model: there are many models of particle physics that go beyond the Standard Model and predict one or more Higgs or Higgs-like particles. To ascertain whether this is the Standard Model Higgs, it has to be observed in all five of the decay modes listed in the previous section.
Since July 2012, a large amount of additional data has been collected, and the search for the Higgs in the lvlv, tautau and bb channels has continued in addition to the two sensitive channels. None of the less sensitive channels is able to discover the Higgs on its own as yet, but some of them show hints of a Higgs signal. With all channels combined, the significance currently stands at 7 sigma, meaning that the probability of the discovery being spurious is 1 part in a trillion!
Another important step is the measurement of the spin and parity quantum numbers of the discovered particle. Any Higgs-like particle must have spin 0, while the Standard Model Higgs must have even parity. These measurements have already started. At this point, it is definitely starting to look like the Standard Model Higgs, or at least a very Standard Model-like Higgs.
What lies ahead…
2012 has been a phenomenal year for us; Higgs search and measurement results using the full 2012 dataset will be presented at major conferences in the spring and summer of 2013. It is expected that these measurements will go a long way toward answering the vital question: is this the Standard Model Higgs?
Notwithstanding, a full closure of the issue will require much more data than we have now. After a two-year break for upgrades, the LHC will start taking data again in 2015, at the substantially higher collision energy of 13 TeV. The event rate will also be higher, leading to a faster accumulation of Higgs-like events. We will be prepared to analyze these events, increase the accuracy of our measurements and explore the Higgs sector in detail.
Throughout all the Higgs excitement, we firmly keep in mind that this is only one of the principal goals of the LHC. High-energy physics at this crossroads faces a number of intriguing questions: What constitutes the so-called Dark Matter? Is SuperSymmetry a fuller explanation of nature than the Standard Model? Are quarks and leptons really elementary particles, or are they composed of something even more fundamental? We will be looking to answer these questions and more as the LHC program continues through the 2010s, the 2020s and possibly the 2030s.
The writer did his undergraduate studies at Yale University, received a PhD in Physics from Harvard University, and is now a postdoctoral researcher with CERN/University of Wisconsin-Madison. He is based at CERN in Geneva, Switzerland.

Toothy Tale Wings and teeth

A newly discovered bird of the dinosaur age, identified from a fossil, had some of the most elaborate teeth ever seen in a bird, scientists say.
What makes it all the more interesting, they add, is that this bird flourished at a time when other bird species had already begun an evolutionary journey toward toothlessness.
"Maybe differences in diet played a part" in explaining the unusual features of the species, said Jingmai O'Connor of the University of Southern California, lead author of a new study on the findings.
Published in the latest issue of the Journal of Vertebrate Paleontology, the analysis suggests the animal, called Sulcavis geeorum, lived on a tough diet that may have included crabs. The researchers believe the teeth of the new specimen greatly increase the known diversity of tooth shape in early birds, and hints at previously unrecognized ecological diversity.
The fossil hails from the early Cretaceous era, an estimated 121-125 million years ago, from what is now Liaoning Province, China. The bird is believed to a member of a lineage known as Enantiornithines, the most numerous birds from the time of the dinosaur.

Space Behemoth Largest spiral galaxy

Astronomers have crowned the universe's largest known spiral galaxy, a spectacular behemoth five times bigger than our own Milky Way.
The title-holder is now NGC 6872, a barred spiral found 212 million light-years away in the southern constellation Pavo, researchers announced on Jan. 10, 2013. The distance between NGC 6872's two huge spiral arms is 522,000 light-years, compared to about 100,000 light-years for the Milky Way.
NGC 6872 has ranked among the largest known spiral galaxies for decades. But it has only now been crowned champion, after detailed study of data gathered by a number of instruments, including NASA's Galaxy Evolution Explorer spacecraft, or GALEX.

What are marsupials?

Marsupials are an infraclass of mammals living primarily in the Southern Hemisphere; a distinctive characteristic, common to most species, is that the young are carried in a pouch. Well-known marsupials include kangaroos, koalas, possums, opossums, wombats and the Tasmanian devil. Marsupials represent the clade originating with the last common ancestor of extant metatherians. Like other mammals in the Metatheria, they are characterized by giving birth to relatively undeveloped young, often residing in a pouch with the parent for a certain time after birth. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with 13 in Central America, and one in North America, north of Mexico.

Konal: A sure hit

Konal was crowned the winner of 'Shera Konthho 2009', beating thousands of other talented singers. Her demand in the media has accelerated since then, as she has swiftly climbed the ladder of popularity.
Music is in Konal's blood -- with her maternal grandfather being an instrumentalist and her mother, a singer. Since childhood, Runa Laila's popular number “Shilpi” has been Konal's favourite song; it was always on her lips.
As fate would have it, Runa Laila was one of the judges at the 'Shera Konthho' competition. Konal said, “It was incredible to have my favourite singer and idol as a judge. I cherished the whole experience very much.”
The latest season of 'Shera Konthho' is on air, with Konal acting as the host this time around. Asked about her sudden interest in anchoring, Konal said although the decision was sudden, her work is being praised by many.
Konal also hosted a Channel i Award show in Singapore recently. She said, “It was a stage presentation. Emceeing a live show was a different kind of experience, as I could interact directly with the audience.”
Offers to host other TV shows are coming aplenty, but the singer is declining them all respectfully. She said, “At this moment, I don't want to host for any other channel except Channel i. I'm hosting 'Shera Konthho' because it is a music- related show.”
Asked what she is achieving by hosting this particular show, Konal replied, “This is definitely a positive addition to my career. I'm learning new things from the judges everyday. My experiences are being enriched. I consider this a great gain.”
Along with stage shows, live TV shows, audio albums and hosting, Konal has done playback singing for over a dozen movies. She has also done several jingles for TV commercials, as well as appearing as a model for five TVCs for Airtel. Konal played a guest role in the movie “Lal Tip”. The singer, however, asserts that she prefers not to take on any new modelling or acting projects.
Her top priority remains music, with her latest album “Konal's Jadu” becoming a hit among the listeners soon after it was released a couple of months ago. The singer is now planning to make music videos of the songs. Konal said she wants to make the album more popular among both the local and international audiences. Her plans also include starting work on the next album, as soon as the 'Shera Konthho competition' wraps up.
Konal grew up in Kuwait. Her family still lives there. The singer has set up temporary lodging at her maternal uncle's home in Dhaka, while she frequently flies to Kuwait whenever she misses her family. Konal is currently studying at the University of Liberal Arts Bangladesh, in the Department of Media Studies and Journalism.

Workshop on miniature painting at Gallery Cosmos-2

Shaheed Colonel Jamil Foundation has organised a 10-day miniature painting workshop at Cosmos Gallery-2, Mohakhali in Dhaka. The workshop was inaugurated on January 11. Pakistani artist Safdar Ali Qureshi is conducting the workshop.
About 25 painters of different age groups are taking part in the workshop. The participating artists are: Pijush Kanti Sarkar, Pronob Kumar Sarkar, Wahida Sultana, Shahnoor Mamun, Sultan Ishtiaque, Tajosh Halder, Ariful Islam, Zeenat Zulfiqure, Sadiya Sultana, Sanjida Sharmeen, Mukti Khatun, Farzana Akhter Tania, Shajib Ahmed, Lamia Azad, Kamrun Nahar, Ashraful Arefin, Tanjima Tabassum, Vinita Karim, Afrozaa Zamil Konka and others. The exhibition is being supported by Cosmos Group.
About the workshop, Sourav Chowdhury, gallery assistant of Cosmos, said, “The workshop reflects our love for art, profound respect for artistic creativity and commitment to bringing about a positive change in society through arts.
“The contemporary miniature work from Pakistan is undoubtedly amazing. Each miniature painting takes two weeks to a month to complete. However, the workshop aims to popularise miniature (the medium) among promising painters here. The technique is very complicated. This medium can effectively depict any subject like aspects of human life, nature, seasons and more.”
The workshop ends on January 20.

Jazz

Jazz is a musical style that originated at the beginning of the 20th century in black communities in the southern United States.
-While jazz is considered difficult to define, improvisation is consistently regarded as being one of its key elements.
-The stylistic origins of the genre belong to Blues-Folk-March-Ragtime.
-Its cultural origins are found in New Orleans, USA.
-Typical instruments for jazz are saxophone, clarinet, flute, vibraphone, trumpet, piano, guitar, banjo, tuba, double bass, bass guitar, trombone and drum kit.
-There are many sub-genres of jazz. Some are: Asian American, Avant-garde, Bebop, Big Band, Chamber, Continental, Cool and Free.
-Among the most influential musicians of the genre are Louis Armstrong, Duke Ellington, Charlie Parker, Miles Davis, Benny Goodman, Coleman Hawkins, Count Basie and John Coltrane.

Facebook ramps up social network search power

Facebook has ramped up its search capabilities at the world's leading social network in a budding challenge to Google, LinkedIn, Yelp and other Internet firms. The "graph search" feature launched in a test version allows Facebook members to delve into the vast amount of information on Facebook, which is not available on Web search engines such as Google. Facebook worked closely with Bing on the search feature that lets people get answers to queries such as "What songs do my friends like?" along with pulling in online information from the Microsoft search engine. "We expanded our relationship with Bing," Facebook engineer Tom Stocky said during a press event at the social network's headquarters in Menlo Park, California, the first major announcement since Facebook went public in May. "We worked closely with Bing to make Web search feel more a part of Facebook." A fledgling version of graph search designed to let Facebook members do natural language searches to find places, pictures, movies and more that their friends liked began rolling out in for US English language users on Tuesday. “We look at Facebook as a big social database," Mark Zuckerberg said. "Just like any database, you should be able to query it."
http://www.thedailystar.net/photo/2013/01/18/2013-01-18__st08.jpg
Personal computer makers, trying to beat back a tablet mania that's eating into their sales, are making what may be a last-ditch attempt to sway customers by mimicking the competition.
Many of the laptops to be unveiled around the world in coming months will be hybrids or "convertibles" - morphing easily between portable tablets and full-powered laptops with a keyboard, industry analysts say.
The wave of hybrids comes as Intel Corp and Microsoft Corp, long the twin leaders of the PC industry, prepare to report results this week and next. Wall Street is predicting flat to sluggish quarterly revenue growth for both, underscoring the plight of an industry that has struggled to innovate.
In 2013, some are hoping that will change.
With the release of Microsoft's touch-centric, re-imagined Windows 8 platform in October and more power-efficient chips from Intel, PC makers are trying to spark growth by focusing on creating slim laptops with touchscreens that convert to tablets and vice versa.
Microsoft, expanding beyond its traditional business of selling software, is expected this month to roll out a "Surface Pro" tablet compatible with legacy PC software developed over decades.
With sales of PCs falling last year for the first time since 2001, this year may usher in a renaissance in design and innovation from manufacturers who previously focused on reducing costs instead of adding new features to entice consumers.

Fujitso New Product


http://www.thedailystar.net/newDesign/photo_gallery.php?pid=265587
Fujitsu Tab
Computer Source Limited (CSL) has brought Fujitsu Stylistic M532 Android tablet in the local market.
The M532 runs on Android 4.0 (Ice Cream Sandwich) and is powered by NVIDIA Tegra Mobile quad-core processor. The tablet has an 8 MP rear-facing camera and a 2MP front-facing camera.
The display size of this Tab is 10.1-inch (1,280-by-800-pixel) and it is multi touch. It has 1GB DDR2 memory, 32GB built-in storage and HDMI, Bluetooth 3.0, docking connector, USB 2 port. It also has Wi-Fi that connects to 802.11b/g/n networks. The M532's video player supports MPEG4, H.264, and VP8 videos. For audio, the M532 supports MP3, AAC, WAV, FLAC or WMA and MIDI, VORBIS.
This Fujitsu Tab also features Google Maps, Google Mail, Google Search, Android browser, Android Market, Think-free Office Mobile as Bundle Software.
The M532 has been designed primarily for business professionals with added security features and above-average durability.
Computer Source Limited, top most ICT Product and Service Distributor in Bangladsh have introduced the M532 Tab in the local market by its country wide distributor channel along with its 37 outlet.
The M532 weighs 560G and its battery supports up to 8. 4 hours.
This Tab has a price tag of Tk 60,500 with one year warranty and Fujitsu sleeve case.
Asus Laptop
Asus' new laptop A44H-B970 is now available in the local market.
The laptop has 14-inch (1366 x 768) display. It is powered by Intel dual core 2.3 GHz processor and features Intel GMA HD Graphics, 2 GB DDR3 RAM, 500 GB hard drive, Wi-Fi(802.11b/g/n), Bluetooth with HDMI support, webcam, USB 3.0 port.
Its smudge-proof palm rest resists fingerprints and helps the laptop retain its appearance all the time. The laptop has a price tag of Tk 34,000