"Long before it's in the papers"
March 07, 2012

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Additional evidence of elusive “God particle” reported

March 7, 2012
Courtesy of Michigan State University
and World Science staff

Af­ter 40 years of search­ing, phys­i­cists say they have have turned up new ev­i­dence for the ex­ist­ence of the elu­sive Higgs bos­on. 

The Higgs bos­on is a hy­po­thet­i­cal par­t­i­cle thought re­spon­si­ble for giv­ing mass to mat­ter. It’s also a crit­i­cal but still un­prov­en com­po­nent of the long-stand­ing Stand­ard Mod­el of par­t­i­cle phys­ics, a work­ing theory most phys­i­cists rely on to ex­plain the make­up of the uni­verse. 

Mich­i­gan State Uni­vers­ity phys­i­cist Wade Fish­er pre­sented the new find­ings March 7 at a phys­ics con­fer­ence in La Thuile, It­a­ly.

If a Higgs bos­on is cre­at­ed in a high-energy par­t­i­cle col­li­sion, it’s ex­pected to break down in­to light­er, more sta­ble par­t­i­cles be­fore even the world’s best de­tec­tors can snap a pic­ture of it. To find one, phys­i­cists re­traced the path of these sec­ond­ary par­t­i­cles and ruled out pro­cesses that mim­ic its sig­nal. 

“We see a dis­tinct Higgs-like sig­na­ture that can­not be easily ex­plained with­out the pres­ence of some­thing new,” said Fish­er, who co­or­di­nates sci­en­tif­ic teams that go by the names Col­lider De­tec­tor at Fer­mi­lab and DZero, at the De­part­ment of En­er­gy’s Fer­mi Na­t­ional Ac­cel­er­a­tor Lab­o­r­a­to­ry. “If what we’re see­ing really is the Higgs bos­on, it will be a ma­jor mile­stone for the world phys­ics com­mun­ity and will place the key­stone in the most suc­cess­ful par­t­i­cle phys­ics the­o­ry in histo­ry.”

The re­sults, which have been col­lect­ed over sev­er­al years at Fer­mi­lab, are si­m­i­lar to those found by teams work­ing at the Large Had­ron Col­lider at CER­N, the Eu­ro­pe­an Or­gan­iz­a­tion for Nu­clear Re­search. But even though the re­sults are close, sci­en­tists are not quite ready to claim a de­fin­i­tive disco­very, said Dmi­tri Denisov, a DZero spokesper­son and phys­i­cist at Fer­mi­lab.

“There is still much work ahead be­fore the sci­en­tif­ic com­mun­ity can say for sure wheth­er the Higgs bos­on ex­ists,” Denisov said. “Based on these ex­cit­ing hints, we are work­ing as quickly as pos­si­ble to fur­ther im­prove our anal­y­sis meth­ods and squeeze the last ounce out of our da­ta.”

The Col­lider De­tec­tor at Fer­mi­lab is an in­terna­t­ional ex­pe­ri­ment of 430 phys­i­cists from 58 in­sti­tu­tions in 15 coun­tries. DZero is an in­terna­t­ional ex­pe­ri­ment con­ducted by 446 phys­i­cists from 82 in­sti­tu­tions in 18 coun­tries.

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After 40 years of searching, physicists say they have have turned up new evidence for the existence of the elusive Higgs boson. Michigan State University physicist Wade Fisher presented the findings March 7 at a physics conference in La Thuile, Italy. The Higgs boson is a hypothetical particle thought responsible for giving mass to matter, a critical but still unproven component of the long-standing Standard Model of particle physics. But if a Higgs boson is created in a high-energy particle collision, it’s expected to break down into lighter, more stable particles before even the world’s best detectors can snap a picture of it. To find one, physicists retraced the path of these secondary particles and ruled out processes that mimic its signal. “We see a distinct Higgs-like signature that cannot be easily explained without the presence of something new,” said Fisher, who coordinates scientific teams that go by the names Collider Detector at Fermilab and DZero, at the Department of Energy’s Fermi National Accelerator Laboratory. “If what we’re seeing really is the Higgs boson, it will be a major milestone for the world physics community and will place the keystone in the most successful particle physics theory in history.” The results, which have been collected over several years at Fermilab, are similar to those found by teams working at the Large Hadron Collider at CERN, the European Organization for Nuclear Research. But even though the results are close, scientists are not quite ready to claim a definitive discovery, said Dmitri Denisov, a DZero spokesperson and physicist at Fermilab. While past findings have also suggested the existence of the Higgs—which otherwise would exist only in theory—”there is still much work ahead before the scientific community can say for sure whether the Higgs boson exists,” Denisov said. “Based on these exciting hints, we are working as quickly as possible to further improve our analysis methods and squeeze the last ounce out of our data.” The Collider Detector at Fermilab is an international experiment of 430 physicists from 58 institutions in 15 countries. DZero is an international experiment conducted by 446 physicists from 82 institutions in 18 countries.