XPP, X-ray Pump Probe ntsuas ntawm Linac Coherent Light Source (LCLS), tau rov qab online thiab txais tos cov kws tshawb fawb tom qab ua tiav rov tsim dua. Kev kho dua tshiab tau nyeem XPP rau qhov kev nce ntxiv hauv X- cov duab hluav taws xob uas xav tau los ntawm kev nce siab ntxiv - lub zog hloov mus rau LCLS ntawm Lub Tsev Haujlwm Saib Xyuas Hluav Taws Xob SLAC National Accelerator Laboratory. LCLS yog ib qho pioneering X-ray free-electron laser chaw siv los ntawm cov kws tshawb fawb thoob ntiaj teb los ntes ultrafast snapshots ntawm cov txheej txheem ntuj.
"Kev ua kom tiav XPP rov tsim dua nyob rau- sijhawm thiab nyob rau- pob nyiaj yog lub sijhawm tseem ceeb rau kev nce qib siab - zog, thiab peb zoo siab heev uas cov cuab yeej rov qab los txhawb cov kws tshawb fawb thoob ntiaj teb," said John Hogan, tus thawj coj ua haujlwm rau LCLS siab - lub zog hloov kho. "Qhov no yog kev siv zog pab pawg loj, koom nrog cov neeg koom tes thoob plaws SLAC engineering, kev tshawb fawb thiab pab pawg ua haujlwm."
Txij li thaum nws qhov kev tshwm sim xyoo 2010, XPP tau ua kom muaj kev tshawb fawb thoob plaws hauv cov ntaub ntawv tshawb fawb -los ntawm quantum cov ntaub ntawv khaws cia rau cov ntaub ntawv dynamics thoob lub sij hawm - nrog rau cov kev tshawb fawb hauv chemistry, physics thiab bioscience. Cov kws tshawb fawb tau siv XPP los ua tus pioneer X-ray optics technologies, nrog rau kab noj hniav-raws li X-ray oscillators uas yog shaping yav tom ntej X-ray dawb-electron laser chaw.
Tsis ntev los no, xyoo -ntev rov tsim kho XPP rau lub siab tom ntej - lub zog hloov mus rau LCLS, uas tau pib xyoo 2025 thiab yuav siv sijhawm li ob xyoos los ua kom tiav. Tom qab kev hloov kho tshiab, LCLS yuav tsim siab - zog X-rays ntawm qhov rov ua dua mus txog ib lab pulses ib ob, ua rau XPP khaws cov ntaub ntawv ntau dua, ua tiav qhov kev daws teeb meem siab dua thiab txhawb ntau qhov kev sim.
"Hauv xyoo 2010, XPP tau dhau los ua thawj lub cuab yeej hauv ntiaj teb siv nyuaj X-rays los ntawm X-ray dawb-electron laser," said Takahiro Sato, XPP cov khoom siv lead ua. "Nws yog ib qho cuab yeej peb tau siv los tsim cov cuab yeej thiab cov tswv yim tshiab thiab nthuav qhia kev tshawb fawb ultrafast. Nrog rau qhov kev hloov kho tshiab no, peb tau ua kom nws nyob twj ywm nyob rau hauv pem hauv ntej ntawm daim teb no."
Txhawm rau npaj XPP rau qhov loj ntawm photons, muaj zog dua thiab cov khoom siv hluav taws xob sib txuas, pawg tau tshem tawm tag nrho cov cuab yeej, tshem tawm cov khoom qub qub thiab rov tsim cov cuab yeej nrog cov khoom tshiab thiab kho dua tshiab.
Ib qho tseem ceeb ntxiv yog qhov Loj Offset Ob Chav Crystal Monochromator, uas yuav yog cryo-cooled siv cov kua nitrogen rau kwv yees li -260℃F txhawm rau tswj cov cua sov ntxiv thiab txo qhov kub ntawm qhov hloov pauv thaum sim.
Pab neeg no kuj tau hloov kho cov txheej txheem multiplexing, uas tuaj yeem faib cov LCLS X-ray beam hauv ob- coj ib lub kwj mus rau XPP thaum xa lwm cov dej ntws mus rau lwm cov twj paj nruag- yog li ntau qhov kev sim tuaj yeem khiav ib zaug. Qhov tshiab multiplexing system hloov qhov qub thiab txhim khu kev qha thiab ruaj khov.
Rebecca Armenta, tus kws tshaj lij ua haujlwm rau XPP tau hais tias "qhov loj - qhov kev tsim kho tshiab no tau tshwm sim hauv qhov chaw ua haujlwm, thiab kuv zoo siab tias peb pab neeg tau ua haujlwm zoo rau lub sijhawm teem sijhawm thiab koom tes nrog lwm pab pawg kom nws tshwm sim," said Rebecca Armenta, tus kws tshaj lij rau XPP rov tsim kho.
XPP tab tom rov qab los ua haujlwm ib txwm nyob rau lub caij nplooj ntoo hlav no thiab yuav pom qhov muaj peev xwm loj ntxiv thaum lub siab - lub zog hluav taws xob tuaj online rau thaum kawg ntawm 2027.
Pab neeg no tseem yuav xaiv cov kev hloov kho dua tshiab thaum lub sijhawm teem tseg rau lub xyoo no, suav nrog kev hloov cov kab hluav taws xob uas twb muaj lawm nrog cov qauv uas yuav sib haum nrog lub zog siab dua thiab txhim kho qhov kho qhov muag twj tso kua mis laser nrog cov txheej txheem tshiab tsim los rau kev hloov kho LCLS.
Diling Zhu, tus kws tshawb fawb txog cov cuab yeej ua haujlwm rau LCLS siab- lub zog hloov kho thiab tus thawj coj faib rau LCLS Science, Kev Tshawb Fawb thiab Kev Txhim Kho Division tau hais tias "Tseem tseem ua haujlwm, tab sis nws zoo heev uas tau pom cov cuab yeej rov qab rau hauv kev pabcuam rau cov neeg siv," said Diling Zhu. "Peb muaj cov neeg koom tes los ntawm thoob plaws lub ntiaj teb uas tau txhawj xeeb tos XPP rov qab los online, thiab peb zoo siab tos txais lawv rov qab los."
