BBC NEWS | Science & Environment | 'Big Bang' experiment starts well 22/10/2009 12:45 BBC NEWS | Science/Nature | Collider halted for months 22/10/2009 12:44

Low graphics Help Search Explore the BBC Low graphics Help Search Explore the BBC

BBC NEWS CHANNEL 2008 was a very exciting year for BBCparticle NEWS CHANNEL physics... (kind of)

News Front Page Page last updated at 11:23 GMT, Wednesday, 10 September 2008News 12:23 Front UK Page Page last updated at 11:55 GMT, Saturday, 20 September 2008 12:55 UK World World E-mail this to a friend Printable version E-mail this to a friend Printable version UK UK 'Big Bang' experiment starts well England halted for months England Northern Ireland Northern Ireland Guide Science Engineering Computing Q&A Analysis Scotland SEE ALSO Scotland By Paul Rincon Wales : Guide introduction 03 Sep 08 | Science/Nature Wales Science reporter, BBC News Business SEE ALSO Earth 'not at risk' from collider Business Politics God discovery 'likely' Scientists have hailed a 23 Jun 08 | Science/Nature Politics Health 10 Sep 08 | Edinburgh, East and Fife Cern lab goes 'colder than space' successful switch-on for an Education Health Large Hadron Collider: Guide introduction 18 Jul 08 | Science/Nature enormous experiment which Science & Environment03 Sep 08 | Science & Environment Education Failure during Cern magnet test will recreate the conditions a Technology Cern lab set for beam milestone 03 Apr 07 | Science/Nature Science & Environment few moments after the Big Entertainment 07 Aug 08 | Science & Environment RELATED INTERNET LINKS Technology Bang. Also in the news Superconducting magnets are cooled down using liquid helium Cern lab goes 'colder than space' LHC (Cern) ------Entertainment 18 Jul 08 | Science & Environment They have now fired two beams Video and Audio The BBC is not responsible for the content of external The Large HadronPage last Collider updated nearat 18:17 Geneva GMT, Monday, will be 17 outNovember of action 2008 for Also in the news ------Earth 'not at risk' from collider internet sites of called around at least two months, the European Organization for Nuclear ------Have Your Say 23 Jun 08 | Science & Environment the 27km-long tunnel which Research (Cern)E-mail says. this to a friend Printable version Video and Audio Magazine Cern particle lab schedule slips TOP SCIENCE & ENVIRONMENT STORIES houses the Large Hadron Collider The LHC has been in construction for ------In Pictures Part of the giantHadron physics experiment Collider was turned repairs off for the weekend cost £14mLeaping wolf snatches photo prize (LHC). some 13 years 25 Jun 07 | Science & Environment Have Your Say while engineers probed a magnet failure. Country Profiles Failure during Cern magnet test Primate fossil 'not an ancestor' Magazine The £5bn machine on the Swiss-French border is designedSpecial to Reports smash India-China climate change deal 03 AprBut 07a Cern| Science spokesman & Environment said damage to the £3.6bn ($6.6bn) particle SEE ALSO In Pictures protons together with cataclysmic force. accelerator was worse than anticipated. | News feeds Related BBC sites Energising the quest for 'big theory' Hadron Collider halted for months 03 Jan 06 | Science & Environment 20 Sep 08 | Country Profiles Scientists hope it will shed light on fundamental questionsSport in physics. The LHC is built to smash protons together at huge speeds, Scientist's promise on collider Special Reports Weather Undergroundrecreating searchconditions for moments'God particle' after the Big Bang. MOST POPULAR STORIES NOW 10 Sep 08 | The first - clockwise - beam completed its first circuit of Radiothe 1 Newsbeat 04 Feb 05 | Science & Environment Scientists hope it will shed light on fundamental questions in physics. SHARED READ WATCHED/LISTENED Related BBC sites CBBC Newsround Large Hadron Collider: Guide introduction underground tunnel at just before 0930 BST. The second - anti- 03 Sep 08 | On This Day RELATED BBC LINKS Retrial for Travolta Bahamas case Sport clockwise - beam successfully circled the ring after 1400 BST. Science & EnvironmentSection damaged Editors' Blog Earth 'not at risk' from collider Weather Big Bang Machine BBC defends BNP move amid protest On Friday, a failure, known as a quench, caused around 100 of the 23 Jun 08 | Radio 1 Newsbeat So far, all the beams have been RELATEDLHC's INTERNET super-cooled LINKS magnets to heat up by as much as 100 degrees. Why exactlyCern do labpeople goes vote 'colder for thanthe BNP? space' CBBC Newsround stopped, or "dumped", after just a We will be looking at what LHC (Cern) Leaping wolf18 snatchesJul 08 | photo prize On This Day the Universe was made of The fire brigade were called out after a tonne of liquid helium leaked Failure during Cern magnet test few circuits. into the tunnel at Cern, near Geneva. Job cuts feared at Land Registry Editors' Blog billionths of a second after the The BBC is not responsible for the content of external 03 Apr 07 | On Thursday, engineers hoped to Big Bang internet sites Brown urges end to postal strike Cern spokesman James Gillies said inject clockwise and anti-clockwise RELATED BBC LINKS on Saturday that the sector that Should Asterix hang up his sword? Dr Tara Shears, University of The £5bn Large Hadron Collider (LHC) is intended to smash protons - one of the BBC - Lyn Evans Profile protons again, but this time they Liverpool TOP SCIENCEwas damaged & ENVIRONMENT buildingwould blockshave ofto STORIES matterbe - into each other UK navy forces to return to Iraq RELATED INTERNET LINKS plan to "close the orbit", letting Leapingwarmed wolf up snatches from its photooperating prize What is the Large Hadron Collider? Top Gear Windows 7:LHC How (Cern) to upgrade your computer the beams run continuously for a temperature -Repairing of near absolute the Large Hadron Collider (LHC) near Geneva will Primate fossil 'not anGet ancestor' your tickets to Top Gear The world'sThe longestBBC is not golf responsible course for the content of external few seconds each. zero - so that costrepairsLIVE almost could £14m be ($21m) and "realistically" take until at least India-China climate change deal internet sites made, and thennext cooled summer down to start back up. Most popular now, in detail The BBC understands that low-energy collisions could happen in the | Newsagain. feeds An electrical failure shut the £3.6bn ($6.6bn) machine down in 1 next few days. This will allow engineers to calibrate instruments, but We need a bomb under lazy FROM OTHER NEWS SITES While he said there was never any will not produce data of scientific interest. orthodoxy that has almost MOSTdanger POPULAR towrecked the STORIES public, English Mr NOWGillies teaching The LHC has been in construction for admitted Minettethat the Marrin breakdown some 13 years "There NEWSit is," COMMENTproject leaderBUSINESS Lyn EvansMONEY saidSPORT whenLIFE the & beamSTYLE TRAVEL DRIVING ARTS & ENTS ARCHIVE SHAREDwould READbe costly.WATCHED/LISTENED What happened in the machine? completed its lap. There were cheers in the control room when OUR PAPERS SUBSCRIPTIONS engineers heard of the successful test. RetrialHe said: for "A Travolta full investigation Bahamas is casestill under way but the most likely UK NEWS WORLD NEWS POLITICS SCIENCE ENVIRONMENT WEATHER TECH & causeWEB seemsVIDEO toPHOTO be a faultyGALLERIES electricalTOPICS connection between two of the Whymagnets exactly which do probably people votemelted, for leadingthe BNP? to a mechanical failure. CouldMOBILE RSS 2009 be a scary year for ? BBC"We're defends investigating BNP move and weamid can't protest really say more than that now. Where am I? Home News UK News Times Online Leaping"But we dowolf know snatches that we photo will haveprize to warm the machine up, make From The Times MY PROFILE SHOP JOBS PROPERTY CLASSIFIEDS Jobthe repair,cuts feared cool itat down, Land andRegistry that's what brings you to two months of September 6, 2008 MOSTdowntime READ forMOST the COMMENTED LHC." UK navy forces to return to Iraq Large Hadron Collider will not turn MOST CURIOUS TODAYBrownLarge urges end Hadron to postal strike Collider: Scientists' world to goo, promise scientists ShouldBNP: Thank Asterix you Auntie hang for up giving his us sword? such a... Fatherwish accused of listabducting for man he the believes... LHC Red for danger: Liverpool empire could be... EXPLORE UK NEWS Windows 7: How to upgrade your computer The 50From Biggest the Movies particle of 2009 that gives everything its mass, to mini CRIME NEWS The world'sblack holeslongest and golf extracourse spatial dimensions, the LHC has the EDUCATION NEWS HEALTH NEWS Most popularpotential now, into detailmake a host of amazing discoveries SCOTLAND NEWS

Ian Sample, science correspondent TIMES RECOMMENDS guardian.co.uk, Wednesday 10 September 2008 13.37 BST

City workers: 'We’re larger | smaller worth our bonuses' MontageThe of 'end key of momentsthe world is from nigh' suspicionsswitch-on have been so powerful that the scientists behind the LHC have published The last of the big jokers a report to allay their fears http://news.bbc.co.uk/1/hi/sci/tech/7626944.stmSeduction cuisine for Page 1 of 2 bachelors IMAGE :3 of 3 http://news.bbc.co.uk/1/hi/sci/tech/7604293.stm Page 1 of 4 COMMENT Joanna Sugden

RECOMMEND?

Cancel your plans for next Wednesday, it could be your FOCUS ZONE last day on Earth. Or could it? If national More reports: If you believe a vocal lobby of doomsayers, at the flick of spending is to go Enjoy further reading from a switch on the Large Hadron Collider (LHC) next week down, the middle Travel to Fashion, Business to the world will be consumed from the inside out and classes must stop Sport, discover more turned to a pile of grey goo. Yesterday their apocalyptic accepting benefits warnings were challenged by a report from the scientists they don’t need behind the project outlining just how safe it is to recreate More... NorthernSimulation Lights of a detectionBusiness ofTravel the Higgs . Photograph: Cern the Big Bang under the France-Switzerland border. Andrew Halden Need to Know Winter Sports When the Large Hadron Collider is up to full power, it will be crashing protons The Large Hadron Collider - the -smashing machine Post a comment More reports built underneath the Alps - has sent more internet-based together 600 million times per second. After each impact, giant detectors will harbingers of doom into a spin than it will have atomic scour the subatomic wreckage looking for evidence of new physics. particles whizzing around its 17-mile circumference when Business city it is put into action next week. They fear that the energies ROYAL MAIL guidesScientists have some pretty good hunches about what the machine might find, released will be so powerful that a runaway black hole Overseas contacts and local businessfrom creating never-seen-before particles to discovering hidden dimensions will be created that will engulf the planet or produce information “quantum strangelets” transforming the Earth into a dead and dark matter, the mysterious substance that makes up 25% of the universe. lump of “strange matter”. Free credit report So worried are they about the impending end of the OnlineSupersymmetry credit history with Universe that they have been to court to try to stop it. CreditExpert from ExperianMany physicists believe that deep down, all the forces of nature are linked, Walter L. Wagner and Luis 2 Sancho in Hawaii sought a including gravity, electromagnetism, the strong force – which binds the temporary restraining order on Two-day national postal Freeconstituents CV Review of atomic nuclei together – and the weak force – which governs scientists at the European Sell yourself! Have your strike begins after radioactive decay in stars. Organisation for Nuclear breakdown of talks CV reviewed by experts Research, or CERN, who they Times Archive, Slide Show One of the most compelling theories that achieves this unification is called 1974: Black holes say have played down the chances that the collider could Findsupersymmetry, an IFA which predicts that every fundamental particle in the may be explosive Find a local independent produce a tiny black hole, PICTURES OF THE DAY financialuniverse advisor has an invisible, overweight twin. The theory has spawned a plethora The young Cambridge which could eat the Earth. astronomer Steve They say that CERN has of bizarre names, such as the squark, the twin of the , and the , Hawking has suggested failed to provide an that these cosmic objects Crossword Club may occasionally destroy environmental impact Sign up today or try one themselves in violent statement as required under explosions the National Environmental Policy Act. The holes that riddle the universe Their objections have been so Hole in space vehement that the scientists discovered behind the LHC have BBC NEWS | Science & Environment | LHC gets colder than deep space 22/10/2009 12:47

Low graphics Help Search Explore the BBC BBC NEWS | Science & Environment | LHC gets warning system upgrade 22/10/2009 14:42

BBC NEWS CHANNEL

Low graphics Help Search Explore the BBC

News Front Page Page last updated at 13:46 GMT, Friday, 16 October 2009 14:46 UK

World E-mail this to a friend Printable version 2009BBC NEWS should CHANNEL be the really exciting UKyear! England LHC gets colder than deep space Northern Ireland By Paul Rincon News Front Page Page last updated at 08:25 GMT, Monday, 28 September 2009 09:25 UK Scotland Science reporter, BBC News SEE ALSO World E-mail this to a friend Printable version Wales Scientist on French terror charge UK Business 12 Oct 09 | Europe England LHC gets warning system upgradeThe Large Hadron Collider at Cern is fired up for first time since 'quench' - TelegraphPolitics 29/10/2009 01:01 LHC gets warning system upgrade 28 Sep 09 | Science & Environment Northern Ireland Games Health By Paul Rincon Collider 'needs warning system' Offers Education Scotland Science reporter, BBC News SEE ALSO 05 Dec 08 | Science & Environment Science & Environment Wales Collider 'needs warning system' Hadron Collider repairs cost £14m est f te eerp ei ru ih bekn es pr, uies aet K n ol nw. Cnet rm te al eerp ad Sna Tlgah esaes n ie fo Tlgah TV. Telegraph from video and newspapers Telegraph Sunday and Telegraph Daily the from Content news. world and UK latest business, sport, news, breaking with Group Media Telegraph the of Website Technology Business 05 Dec 08 | Science & Environment 17 Nov 08 | Science & Environment Entertainment Collider halted until next year Politics Hadron Collider repairs cost £14m The Large Hadron Collider at Cern is fired up for 23 Sep 08 | Science & Environment 17 Nov 08 | Science & Environment Also in the news Health Jobs ------What happened to the Big Bang machine? Collider halted until next year Education first Datingtime since 'quench' Video and Audio 20 Sep 08 | Science & Environment 23 Sep 08 | Science & Environment ------Science & Environment Games Hadron Collider halted for months

What happened to the Big Bang machine?Have Your Say 20 Sep 08 | Science & Environment Technology The Large Offers Hadron20 Sep Collider 08 | Science at &Cern Environment in Geneva has been fired up for the first time Magazine Large Hadron Collider: Guide introduction Entertainment since its high-profileHadron failureCollider halted last year.for months In Pictures 03 Sep 08 | Science & Environment 20 Sep 08 | Science & Environment Also in the news Country Profiles RELATED INTERNET LINKS ------Large Hadron Collider: Guide introduction The giant Atlas detector will search for hints of the elusive particle Special Reports Video and Audio The Large03 Sep Hadron 08 | Science & Environment Collider at Cern is fired up for Large Hadron Collider (LHC) By Tom Chivers ------Related BBC sites The Large Hadron Collider (LHC) experiment has once again The BBC is not responsible for the content of external RELATED INTERNET LINKS Have Your Say Published:first time 12:32PM since GMT 27 Oct 'quench' 2009 Sport become one of the coldest places in the Universe. internet sites Magazine Large Hadron Collider (LHC) Weather All eight sectors of the LHC have now been cooled to their operating Radio 1 Newsbeat TOP SCIENCE & ENVIRONMENT STORIES In Pictures The Large HadronThe BBC isCollider not responsible at forCern the content in Geneva of external has been fired uptemperature for the firstof 1.9 time kelvin (-271C; -456F) - colder than deep space. Cern has spent about 40m Swiss Francs (£24m) on repairs to theThe LHC huge particleinternet sites CBBC Newsround Leaping wolf snatches photo prize Country Profiles since its high-profile failure last year. On This Day accelerator The large magnets that bend particle beams around the LHC are Primate fossil 'not an ancestor' Special Reports Editors' Blog Engineers hope an early warning system being installedsuccessfully at the TOP SCIENCE & ENVIRONMENT STORIES kept at this frigid temperature using liquid helium. India-China climate change deal Large Hadron Collider could prevent incidents of the kind Related BBC sites powered some Leaping wolf snatches photo prize The magnets are arranged end-to-end in a 27km-long circular tunnel | News feeds Sport which shut the machine last year. By Tom Chivers Primate fossil 'not an ancestor' straddling the Franco-Swiss border. protons and lead Weather Published: 12:32PMIndia-China GMT 27 climate Oct 2009change deal MOST POPULAR STORIES NOW The helium leak last September, which resulted from a "faulty splice" The cool-down is an important milestone ahead of the collider's Radio 1 Newsbeat ions around short between magnets, has delayed the start of science operations by | News feeds scheduled re-start in the latter half of November. CBBC Newsround SHARED READ WATCHED/LISTENED more than a year. sections of its 17- On This Day mileThe ring huge on particle The LHC has been shut down Retrial for Travolta Bahamas case Editors' Blog Officials aim to re-start the collider, known as the LHC, in mid- MOST POPULAR STORIES NOW since 19 September 2008, when a It's a bit like firing knitting Friday,accelerator and needles from across the Atlantic Why exactly do people vote for the BNP? November. magnet problem called a "quench" and getting them to collide half SHARED READ WATCHED/LISTENED everythingsuccessfully seemed caused a tonne of liquid helium to way BBC defends BNP move amid protest The vast physics lab is built inside a 27km-long circular poweredtunnel some leak into the LHC tunnel. Leaping wolf snatches photo prize to be working How the recession has changed your High James Gillies, director of straddling the French-Swiss border near Geneva. correctly.protons and lead Street After the accident, the particle communications, Cern Job cuts feared at Land Registry The LHC will send two beams of particles crashing into eachions aroundother at short BBC defends BNP move amid protest accelerator had to be warmed up BBC Radio 4 Material World: One Should Asterix hang up his sword? so that repairs could take place. year on from the LHC's switch-on close to the speed of light. Scientists hope to see newEngineers particlessections in of and its 17- Why exactly do people vote for the BNP? UK navy forces to return to Iraq the debris of these collisions, revealing fundamental new insights into scientistsmile ring on Retrial for Travolta Bahamas case The most powerful physics experiment ever built, the Large Hadron Windows 7: How to upgrade your computer the nature of the cosmos and how it came into being. Collider will recreate the conditions just after the Big Bang. It is Friday, and Brown urges end to postal strike Brown urges end to postal strike This LHC "ring" is split into eight operated by the European Organization for Nuclear Research (Cern), everything seemed UK navy forces to return to Iraq The world's longest golf course distinct parts, or sectors. Six of It will allow us to The cross-section of the ion beam flowing through the LHC, just beforebased thein Geneva. ALICE detector constantly monitor the status of to be working GoodyPhoto: effectCERN 'boosts screening' these are now at or close to their the interconnections Two beams of protons will be fired down pipes running through the Most popular now, in detail operating temperature of 1.9 (http://http://www.telegraph.co.uk/science/)correctly. US paper seeks pothave correspondent been warily putting it through its pacesmagnets. for the These first beams time will travel in opposite directions around the kelvin (-271C; -456F). Gianluigi Arduini, Cern main "ring" at close to the speed of light. since its catastrophicThe breakdown, world's longest or “quench”, golf course which happened when two of the LHC BBC Radio 4 MaterialEngineers World: One and Engineers are powering up year on from the LHC's(http://www.telegraph.co.uk/science/large-hadron-collider/) switch-on Leaping wolf snatches photo prize ’s huge superconducting magnetsAt allotted suffered points around a short the tunnel, the beams cross paths, scientists smashing into one another with cataclysmic energy. Scientists hope magnets in three sectors to circuit within days of it powering up (/science/large-hadron-collider/3352108/Large-Hadron-Collider-broke-down- to see new particles in the debris of these collisions, revealing prepare for the injection of proton beams into the ring. Most popular now, in detail hours-after-launch.html) . fundamental new insights into the nature of the cosmos. A low-intensity beam could be injected into the LHC in the second The cross-section of the ion beam flowing through the LHC, just before the ALICE detector Awesome energy half of October, officials told the BBC. Photo: CERN (http://http://www.telegraph.co.uk/science/) have been warily putting it through its pacesThe operating for the temperaturefirst time of the LHC is just a shade above This beam test would involve only parts of the collider, rather than 3 since its catastrophic breakdown, or “quench”, which happened when two "absoluteof the LHC zero" (-273.15C) - the coldest temperature possible. By the whole "ring". If all goes to plan, the first beam collisions could comparison, the temperature in remote regions of outer space is occur before the end of the year. (http://www.telegraph.co.uk/science/large-hadron-collider/) ’s huge superconducting magnets suffered a short Machine repairs circuit within days of it powering up (/science/large-hadron-collider/3352108/Large-Hadron-Collider-broke-down-http://news.bbc.co.uk/1/hi/sci/tech/8309875.stm Page 1 of 3 hours-after-launch.html) . The collider has been shut down since 19 September 2008, when a magnet problem called a "quench" caused a tonne of liquid helium to leak into the LHC tunnel. Home Studying Research People News & Events About An investigation carried out for the European Organization for http://www.telegraph.co.uk/science/large-hadron-collider/6445829/Th…adron-Collider-at-Cern-is-fired-up-for-first-time-since-quench.html Page 1 of 4 Nuclear Research (Cern), confirmed the cause of the accident was an electrical fault in one of the splices, or "interconnects", linking Go Contact us http://news.bbc.co.uk/1/hi/8270427.stm Page 1 of 3 News & Events

News & events Home News & Events Edinburgh joins the ATLAS collaboration Latest news Edinburgh joins the ATLAS collaboration News archive Published on Tue, 20 Oct, 2009 at 15:36 Upcoming events Physicists from Edinburgh are to join the quest Event calendar for the Higgs boson particle at CERN in General interest Switzerland.

seminars The researchers will join the international ATLAS Previous seminars & collaboration seeking to verify the existence of the theoretical sub-atomic particle, a crucial part podcasts of the of Particle Physics and Cosmology. The ATLAS detector (toroidal magnet system) The ATLAS experiment aims to address the most important unsolved questions in the universe, i.e., whether or not, the Higgs Hot off the press: boson exists, and what the fundamental particle mass generation mechanism is. It could also discover the origin of dark matter and new physics models of nature Edinburgh joins (e.g. super-symmetry). Higgs theory the LHC effort! Emeritus Professor Peter Higgs predicted the existence of the Higgs particle while working at the University in the 1960s. If experiments at CERN’s massive atom-smasher prove the Professor’s theory correct, he is tipped to win the Nobel Prize for physics.

Joining the research at CERN are Dr Philip Clark, Dr Victoria Martin, Dr Andy Buckley, Dr Wahid Bhimji and Dr Andy Washbrook together with students Ben Wynne, Ben Smart and Brendan O’Brien and technician Andrew Main.

They will work on the ATLAS detector, one of four experiments analysising collisions at the Large Hadron Collider as it aims to recreate the conditions of the Big Bang.

Impact of research

Their work will involve modelling and simulating the particle collision process in order to understand the detector response and the complex data produced by the experiments. They will also contribute to the operation of the detector itself and provide software to manage the data produced.

Global partnership 4 Physicists from Edinburgh are already involved in another project at CERN (LHCb) but, until now, have not taken part directly in the search for the Higgs Boson.

The Edinburgh team joins the collaboration, involving 2900 people in 37 countries, after a year of preparatory work with support from colleagues in the Scottish Universities Physics Alliance. Subatomic Physics: Particle Physics Lectures “Physics of the Large Hadron Collider”

5

Particle Physics Lectures Outline

Lecture 1 - Introduction Lecture 6 - Particle Physics at Past Colliders The Standard Model of particle physics The Large Collider The fundamental particles and forces Evidence for and colour + ! Lecture 2 - Practical Particle Physics e e → Measuring particle physics Lecture 7 - Protons, Quarks and Strong Interactions Units, decays, scattering , hadronisation Quantum numbers Quark Confinement Lecture 3 - Quantum Electrodynamics (QED) Running coupling constant Anti-particles Lecture 8 - Weak Interactions Quantum description of electromagnetism and decay Feynman diagrams Weak quark decays Lecture 4 - The LHC Lecture 9 - Electroweak and the Higgs boson Particle acceleration W and Z Colliders The Higgs mechanism Lecture 5 - The ATLAS Detector Lecture 10 - Beyond the Standard Model Interactions of particles in matter Supersymmetry Collider Detectors Extra dimensions ...

6 Particle Physics and Me Dr Victoria Martin CDF JCMB room 5419 [email protected] My research deals with Particle Physics at Colliders. p p I’m currently involved with three projects: 1.96 TeV

1. The CDF experiment at the Tevatron, near Chicago. The Tevatron collides protons and anti-protons at ~2TeV.

2. The ATLAS experiment at the Large Hadron Collider. The LHC collides protons on protons at 14 TeV.

3. The international linear collider (ILC). Design is to collide and at 0.5 - 1 TeV (or more?)

7

Books etc • In conjunction with attending the lectures you will need to read around the subject to fully understand the material. Most up to date: • Level of this course: Particle Physics, by B.R. Martin & G. Shaw, 3rd edition (Wiley 2008) - 10 copies in JCM Library • More advanced: Introduction to Elementary Particles by D. Griffiths, 2nd edition (Wiley 2008) - 4 copies in JCM Library Oldies (but goodies): • Introduction to High Energy Physics - D.H. Perkins, 4th edition (CUP 2000) • Quarks and –F. Halzen & A.D. Martin (Wiley 1984) Further Resources: • For more information that you could ever need on every particle ever: http://durpdg.dur.ac.uk/lbl/ • Information about LHC and LHC physics: www..ch www.atlas.ch

8 Subatomic Physics: Particle Physics Lecture 1 Our current understanding: “The Standard Model of Particle Physics”

9

From the Atom to Subatomic from introductory Subatomic slides atom

nucleus Nuclear } Physics protons & Particle Physics quarks & } electrons

10 !"#$#%&'(&%)*+History,-"&.-//,"&01-* 2$of"')% 3the4 UniverseN%,"$@<&/#.,&-%3&3,%7#/@&7*-+,7

GCH 5%#6,"7,&$',7&/8"')$8& from introductoryU@9#*-+&,%, "$@&7*-+,&#%& EF 7 7)9,"(-7/&#%(+-/#'% %)*+,#&0X,Y4&.)*8& Subatomic8 #$slides8,"&/8-%&#%&-/'.#*&*-7,& EFGHI7 EFIK&'L :'7/&#%(+-/#'%&; 7')9&'(& 0,Y4B&Z#(,/#.,7&'(&,R*#/,3& ,+,*/"'%7<&=)-"27&-%3& 7/-/,7&-",&/@9#*-++@&'(& '/8,"&9-"/#*+,7 Particle '"3,"&EFGEI 7&*'.9-",3& Physics O#/8&EFGM&7&('"&-/'.#*& EFGJ7 EFEH&'L >)-"27&*+).9&#%/'&9"'/'%7 98@7#*7& -%3&%,)/"'%7 } Nuclear EFI 7 EFM&'L ?)9,"8'/&('$&09"'/'%7& [)*+,#&-",&3,%7,&'AT,*/7\ -%3&,+,*/"'%7&%'/&@,/&A')%3& Physics E*.H&8-7&.-77&]&IBHREFEE& #%/'&-/'.74B&:"#.'"3#-+& 2$&0,=)#6-+,%/&/'&JHF& %)*+,'7@7%/8,7#7&0)9&/'&CD,4 } ,.9#",&7/-/,&A)#+3#%$7^^4

V HREF @" EFV&'L N+,*/"'%7&*'.A#%,&O#/8& 9"'/'%7&-%3&%,)/"'%7&/' SubatomicU8,&*'+ +#physics7#'%7&'(&%)* looks+,'%7&#%& /at:8,&%)*+,)7&-",&"-",+@&'(& ('".&-/'.7&0D<&D,4 7)((#*#,%/&,%,"$@&/'&,R*#/,&/8,&9"'/'%7P%,)/"'%7 (very)∴ /8 ,short@&-",&-& 6distances,"@&,((,*/#6,&3,$",,&'(&(",,3'.&/'& EREFW @" GIFF&'L ?/-"PQ-+-R@&('".-/#'%& • 3,7*"#A,&%)*+,# 7@%/8,7#7&'(&8,-6#,"&%)*+,# •(very) early time_8#/, &in`O -"the( [,)/"'%&7/-" 1+-*2&8'+, EVREFW @" GIKF&'L S#"7/&7/-"7&3#,&-%3&,T,*/& universe?'+#3&7/-/, 8,-6@&%)*+,#&#%/'&79-*,&; ()"/8,"&7/-"&('".-/#'%&0-%3& •(very) high energy densities 9+-%,/74

H EFF EFV EFEF EFEV $P*. 3,%7#/@

U#., O-/," [)*+,-"&.-//," 11

The Standard Model The current understanding of the fundamental particles and the interactions between them is called the “Standard Model of Particle Physics”. Boson-mediated FORCES

Gravity ?

Electro- ! magnetism

W± Weak Z0

Strong gluons

12 Basic Particles (1st Generation)

! The particles that you know already, e.g. from beta decay: n ! p e "#e Leptons Basic Constituents of Matter Electron and Four spin-"ℏ Electric Quarks Particle Symbol Type are bounds Charge states of up-quarks electron e" -1 and down-quarks neutrino #e 0 lepton up-quark u +2/3 quark down-quark d !1/3 quark

! • description of beta decay: n ! p e "#e ! • Particle physics description of beta decay: d ! u e "#e •In addition to electric charge, every quarks carries an additional “colour charge” quantum number: either red, blue or green.

13

Higher Generations

Nature replicates itself: there are three generations of quarks and leptons

1st Generation 2nd Generation 3rd Generation charge,e electron e" muon $" tau %" -1 electron muon 0 neutrino #e neutrino #$ #% strange bottom !⅓ d quark s quark b u c t +⅔ Ordinary Matter: built from the 1st generation

Higher Generations: " Why 3 generations? • copies of (#e, e , u, d) • undergo identical interactions symmetry/structure not • only difference is mass of particles understood! • generations are successively heavier

14

Combining relativity and quantum mechanics implies More in PP Lec 2 (& every particle has a corresponding Quantum Physics §14.5) Antiparticles of the SM particles are antimatter

Compared to its matter partner, an antiparticle has: “Track” left by a equal mass • positron •opposite electric charge •opposite “additive” quantum numbers

Example: positron (e+) antiparticle of the electron (“anti-electron”) Discovered in 1931 by Carl Anderson

Notation: bar over symbol or minus ↔ plus + e.g. for first generation: u u¯ d d¯ e− e ν ν¯ ↔ ↔ ↔ e ↔ e 15

Subatomic Forces from introductory Subatomic slides

•At subatomic scales interactions between particles and nuclei are caused by the three subatomic forces: •The electromagnetic force •The weak nuclear force •The strong nuclear force

•The interactions due to these forces are evident in: •Scattering: e.g. scattering of protons on protons at the LHC •Particle Decay: e.g. decay of radioactive nuclei, decays of cosmic- ray •Nuclear Fission and Fusion, e.g.: reactions in a nuclear reactor 235U+n 236U 144Ba +89 Kr + 3n 92 → 92 → 56 36

16 The Forces of Particle Physics Strong Electromagnetic • Strongest force • 2nd strongest force • Acts on quarks only • Acts on charged particles • propagated by (8) gluons, g • propagated by photon, $ Weak Gravity • 3rd strongest force • weakest force - negligible at PP • Acts on all particles scale • propagated by W± and Z0 bosons • Acts on all particles

• Quantum mechanical description uses “messenger particles” to propagate the 6 force between particles. Summary of Standard Model Vertices Messenger particles are spin-1 bosons • ℏ ! At this point have discussed all fundamental fermions ! and their interactions with the force carrying bosons. • e.g. beta decay n!p e "#e propagated by a W! boson ! Interactions characterized by SM vertices time ELECTROMAGNETIC (QED) 6 23 - 17 e q Summary ofHigherStandarOrdderModelsCouplesV toe CHARGErtices - e Q e ! eAt this point haveqdiscussed all fundamentalDoes NOT changefermions So far only considered lowest orFLAVOURder term in the and theire2 interactions with the force carrying bosons. α = γ γ What do the particlesperturbation! Interactions4π series.characteriz do?Highered by SMorderverticesterms also STRONG (QCD) contribELECTRute OMAGNETIC (QED) see: JH D&R lectures 2, 14, 15 - q Couplestime to COLOUR Lowest Order: e + q Couples+ to CHARGE e gs µ - e q Q e Does NOT change Particles interact via one of the forces: strong,e q γ FLAVOURDoes NOT change g 2 electromagnetic or weak. 2s FLAVOUR αs = e g α = 4π γ - γ - WEAK4πChargede Current µ STRONG (QCD) u Two main interactions: νe d’ Changes FLAVOUR g V q Couples to COLOUR - gw w ckm Particle scattering e d u g For"# QUARKS: coupling • Second Order: q s Doese NOT change + + - + BETWEEN+ generations can be elastic or inelastic g 2 W + FLAVOUR • e α =g w2 µ e W Wµ α w = 4sπ g •we’ll mainly consider inelastic scatterings 4π +.... WEAK CharNeutralgedCurrentCurrent e! e.g. scattering of electron and positron,- -- - - • e µe ν, νe e d’qµ producing a pair of muons e+e!%µ+µ! - e "µ Changes FLAVOUR e , νeg ! g V - w µ w ckm Does NOT change e uq For"# eQUARKS: coupling FLAVOUR 0- BETWEEN generations g 2 ZW 0+ Particle decay Third Oαr der:= w W ZW • w 4π ! Dr M.A. Thomson Lent 2004 •e.g. Beta decay: d ! u e "#e We’llWEAK learnNeutral all aboutCurrent ! - e+.... ! ! these type ofe diagrams, ν q •e.g. Muon decay: µ %e "#e "µ - e throughoute , νe the course q Does NOT change 18 0 FLAVOUR Z Z0

SecondDr M.A. Thomsonorder suppressed by relative to firLentst2004 order. Provided is small, i.e. perturbation is small, lowest order dominates.

Dr M.A. Thomson Lent 2004 Hadrons: &

• Free quarks have never been observed - quarks are locked inside hadrons • Hadrons are bound states of quarks: either (qqq) or (qq̅) • Charge of hadron is always integer multiple of electric charge, e • Colour charge of hadron is always neutral • Two types of hadrons – mesons and baryons (also anti-baryons! qq͞ q͞ )

Baryons = qqq Mesons = qq̅ Three quark bound states Bound states of quark anti-quark pair Fermions: spin 1/2ℏ, 3/2ℏ ... Bosons: spin 0, 1ℏ, 2ℏ e.g. proton (uud), (udd) e.g. q anti-baryons e.g. anti-proton π+ = (ud)¯ q̅ p = (uud) π− = (u¯d) q 1 q n = (udd) π0 = (uu¯ dd)¯ q ¯ √2 − • p¯ = (u¯u¯d)

19

Summary The Standard Model of Particle Physics An elegant theory that describes accurately (almost) all measurements in particle physics Matter Forces • fermions, spin-"ℏ •mediated by the exchange of spin-1 bosons • 3 generations of quarks & leptons ℏ e Gauge Charge, Quarks and Leptons Charge, Interaction Bosons e "e "µ "& 0 e µ & !1 Strong gluons, g 0 Electro- u c t +2/3 Photon, $ 0 d s b !1/3 magnetic • Antimatter partner for each Weak W, Z 0, ±1 Gravity ? 0 • Quarks bind together to form hadrons - mesons and baryons 20