2. rész
Kozmológia a 21. században
A táguló Világegyetem Ha a Világegyetem valóban tágul, akkor régen „kisebb”, ezért melegebb volt • A hőmérséklet a mérettel fordítottan arányos az elegendően forró VE-t elektromágneses plazma töltötte ki, amelynek hűlése során kialakultak az atomok és a mindent kitöltő
! kozmikus elektromágneses háttérsugárzás
A kozmikus sugárzás felfedezése • 1965: A. Penzias és R. Wilson (Bell Lab) érzékeny mikrohullámú antennája
A kozmikus sugárzás • 1965: A. Penzias és R. Wilson érzékeny mikrohullámú antennája – iránytól – napszaktól, évszaktól független elektromágneses sugárzást észleltek • Az antenna hibáját kizárták Mi lehet a titokzatos sugárzás forrása? • Mi már sejtjük: A VE-t az első perceiben elektromágneses sugárzás töltötte ki, ami azóta is ott van, csak hullámhossza a tágulás arányában megnőtt Penzias és Wilson mérése szerint a sugárzás hőmérséklete 3,5 K (11. kérdés: Mit jelent ez?)
intenzitás
A hőmérsékleti sugárzás intenzitásának hullámhosszfüggése
hullámhossz ~10cm alatt a légkör átlátszatlan Földről csak az eloszlás maximumától jobbra eső rész mérhető
Irány a világűr:
A Cosmic Background Explorer űrszonda FIRAS = Far Infrared Absolute Spectrophotometer DMR = Differential Microwave Radiometer DIRBE = Diffuse Infrared Background Experiment
!
A FIRAS spektrum
Valaha látott legtökéletesebb hőmérsékleti sugárzási spektrum
A CoBE által mért sugárzási görbe
sugárzás intenzitása
hullámhossz
Planck-görbe
frekvencia
A FIRAS spektrum A hőmérsékleti sugárzás spektrumát a Planckféle eloszlás írja le
(kT )4 x3 dx d"(f, T ) = 8⇡ 3 ex (hc) 1 Z 1
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d"(f, T ) (kT ) = 8⇡ hf (hc)3
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12. kérdés: Mekkora a nukleáris részecske/foton arány?
Izotrópnak látta-e a COBE VE-t?
A Tejút hatását le kell vonni
Izotrópnak látta-e a COBE VE-t?
A dipólus anizotrópia a Föld mozgásának következménye (szintén le kell vonni)
A COBE felfedezése
A piros és kék tartományok hőmérséklet különbsége 10-5K (0,01mm-es hullámok az uszodában)
Multipólus sorfejtés
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Egy dia a 2009-es előadásomból A kozmikus zene „hangszíne” (a háttérsugárzás hatványspektruma) Az első csúcs helye Ω-tól függ
A magasság ΩB függvénye
ℓ∑ a 2ℓm m
T (ϑ, ϕ ) = ∑ aℓmYℓm (ϑ, ϕ ) ℓm
14
A CMB hatványspektruma
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Felső légköri kísérletek
BOOMERanG
Maxima EPSHEP Cocconi-prize 2011: ,,a kozmikus háttérsugárzás anizotrópiájának tanulmányozásában elért kimagasló eredményeikért’’
Kísérlet a világűrben
PLANCK
Kísérletek az Antarktiszon
SOUTH DASI POLE ACBAR QUAD BICEP SPUD
Tiszta égbolt
További kísérletek: Andok tetején (Atacama, Cerro Toco)
Vonzó tiszta égbolt
ACT
Az újszülött VE egyre szebb képe COBE 1992
WMAP 2003
PLANCK 2013
~7°
ACT, SPT ...
~0.3° ~0.1°
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Temperature distribution of CMB
Hatványspektrum aPlanck Planck szerint Planck Collaboration: The mission Angular scale 90
18
2
10
1
0.2
0.1
0.07
6000 5000
D [µK2]
4000 3000 2000 1000 0
50
500
1000
1500
2000
2500
Multipole moment, Fig. 19. The temperature angular power spectrum of the primary CMB from Planck, showing a precise measurement of seven acoustic peaks, that are well fit by a simple six-parameter ⇤CDM theoretical model (the model plotted is the one labelled [Planck+WP+highL] in Planck Collaboration XVI (2013)). The shaded area around the best-fit curve represents cosmic variance, including the sky cut used. The error bars on individual points also include cosmic variance. The horizontal axis is logarithmic up to ` = 50, and linear beyond. The vertical scale is `(` + 1)Cl /2⇡. The measured spectrum shown here is exactly the same as the one shown in Fig. 1 of Planck Collaboration XVI (2013), but it has been rebinned to show better the low-` region.
Az ismert hatványspektrum Planck Collaboration: The Planck mission 104 Planck WMAP9 ACT SPT
D [µK2]
103
102
2 100
500
1000
1500
2000
2500
3000
Fig. 25. Measured angular power spectra of Planck, WMAP9, ACT, and SPT. The model plotted is Planck’s best-fit model including Planck temperature, WMAP polarization, ACT, and SPT (the model is labelled [Planck+WP+HighL] in Planck Collaboration XVI (2013)). Error bars include cosmic variance. The horizontal axis is `0.8 .
Modelljóslatok hatványspektrumra (ΛCDM: hat-paraméteres illesztés)
Győztes
A hatványspektrumból nyerhető adatok Az első csúcs helye Ω-tól függ
A magasság ΩΛ függvénye
A magasság ΩB függvénye
A magasságok Ωm függvényei
Hatványspektrum aPlanck Planck szerint Planck Collaboration: The mission Angular scale 90
18
1
0.2
6000
0.1
0.07
6 paraméterrel illesztett ΛCDM model
5000
D [µK2]
4000 3000 2000 1000 0
2
10
50
500
1000
1500
2000
2500
Multipole moment, Fig. 19. The temperature angular power spectrum of the primary CMB from Planck, showing a precise measurement of seven acoustic peaks, that are well fit by a simple six-parameter ⇤CDM theoretical model (the model plotted is the one labelled [Planck+WP+highL] in Planck Collaboration XVI (2013)). The shaded area around the best-fit curve represents cosmic variance, including the sky cut used. The error bars on individual points also include cosmic variance. The horizontal axis is logarithmic up to ` = 50, and linear beyond. The vertical scale is `(` + 1)Cl /2⇡. The measured spectrum shown here is exactly the same as the one shown in Fig. 1 of Planck Collaboration XVI (2013), but it has been rebinned to show better the low-` region.
A három nagyágyú: SNIa, CMB, BAO
Mi a sötét energia? • A sötét energia a VE gyorsuló tágulásának egy lehetséges és népszerű magyarázata. • Két változatát képzelik – Kozmológiai állandó, ami a teret mindenütt kitöltő homogén energiasűrűség – Mindent kitöltő homogén skalármező (nem a Higgs!) • Állapotegyenlet (nyomás ∝ energiasűrűség) p=wε – 13. kérdés: Mekkora w nem-relativisztikus ideális gáz esetén? – Relativisztikus ideális gáz: w=1/3 – Kozmológiai állandó: w=-1
A három nagyágyú: SNIa, CMB, BAO
Hubble Hubblediagram diagram (740SN SNIa)Ia) 2015: (740 Hubble-tv
Betoule et al.et2014 (JLA) Betoule al. 2014 (JLA)
w-Ωm diagram
DarkDark Energy equation of state Energy equation of state W= W= pressure/density pressure/density (cosmological constant W=-1) (cosmological constant W=-1)6
6
Kozmológiai paraméterek mennyiség
2003
2015 (Planck+…)
H
71
67.74±0.46 km/s/Mpc
Ω
1.02±0.02
1.000±0.009
Ω
0.27±0.04
0.3089±0.0062
Ω
0.044±0.004
0.0501±0.0003
Ω
0.73±0.04
0.6911±0.0062
T
(13.7±0.2) Gév
(13.799±0.021) Gév
T
(379±8) ezer év
Mi lehet a sötét anyag? VE-ben keressük: • Barionos: önálló kutatási területek – bolygók – fehér törpék – MACHO-k (Massive Compact Halo Object): barna, fekete törpék, neutroncsillagok, fekete lyukak – gázfelhők • WIMP-ek
Laboratóriumban keressük: • Nem barionos (ismeretlen), gyengén hat kölcsön a barionos anyaggal – „forró” (közel fénysebességű, HDM): neutrínók (kevés) – „hideg” (lassú, CDM): Weakly Interacting Massive Particle (WIMP) Részecskefizikusok kedvence, de egyelőre nem sikerült találni
Netalán a gravitáció módosul nagy skálán?
Wide range of parameters!
Direct generally ...dedetection van soksearches más javaslat is optimised for W
Legnépszerűbb WIMP: LSP • D = R = (-1)3B+2S+L R-paritás – 13+1. kérdés: Mekkora az u-kvark és a muon R-paritása? – R = -1 s-fermionokra • Ha a legkönnyebb s-részecske semleges (neutralínó), akkor SA jelölt • Az ilyen s-részecske közvetve felfedezhető az LHC-n (hiányzó energia a jele)
Egy minimális lehetőség: inert Higgs • A SM Higgs-mechanizmus minimális kiterjesztése feltételezett D-szimmetriával – A D = -1-es Higgs-részecske az SA jelölt (fermionokkal nem hat kölcsön)
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Various combinations Now convert the high‐energy / of as arising from exchange of a scalar of mass M , is similar but t ⌅(j , E ) < 0.5. Any further jets Section 4 we will discuss the effect of a light mediator. T ⌅(j , E ) < 0.5. Any further 2 2 limit on into limits on , 2 Tbetween Operator O1 leads to spin-independent coupling the DM an / The cuts used by CMS are simila ‐Nucleon and H H χχ ¯ appearing up to the dimension six level. While are selected by requiring E > 150 GeV an Section 4 we will disc T Figure 1: Dark matter production in association with a single jet in a hadron collider. Both ATLAS and CMS impose additional areof vetoedoperators if SM they contain a second that jet with p (jwill ) > 30 Ge jel a világűrből WIMP Foc This isOperator a representative set SM DM coupling. Various combinations Focus limit on into limits on , SM by converting quark‐level to Operator O could arise from exchange of aG | (j )| < 2.4. A second jet with p (j )one > 3G / O is generated through axial-vector exchange and gives a spin-dep Here we take q = u, d, s and turn on each operator one at ‐Nucleon 1 are selected by requiring E > 1 2150 T> since they would not have awe large impact 3 of as arising from ex ¯ / Section 4 will T Here we take q = u, d, s and turn on each operator under the SM such as squarks in supersym veryHighPT Selection requires E 300 This is a represe / T of as arising from exchange of a scalar of mass M , O is similar but oc † / HighPT Selection requires E > 220 GeV, one jet with p (j ) > F scenarios. Majorana dark matter will yield similar result (th veryHighPT Selection requires E > 2 This is a rep q Tq 2E Nucleo † q Nucleon‐level matrix elements: the leading jet is ⌅(j , j ) < 2.0 radians. andweHleave ¯their appearing theare dimension six level. W 1 2 studyby converting quark‐level to andup thetostudy of operators involving the under the SM such as squarks in sup (a(jw 4 H χχ | vetoed (j1events )|if < 2.4. A second jet Nu there is avetoed second jet | (jiswith )| a<(a 4.5pand are if with there second T sim
for dark matter searches at hadron colliders inv[3, 4]. The signal would m / T ) events over the Standard Model b of jets plus missing energy (j + E inv ⇤) + j final states. In the latter c mainly of (Z ⇤⇤) + j and (W 2 of 2T j + lost, as indicated by the superscript “inv”. Experimental studies performed by CDF [22], CMS [23] and ATLAS [24, 25], mostly in the co Our analysis1will, for the most part, be based on the ATLAS search [ 1 1 of data, although we will also compare to the earlier CM jets in 1 fb 1 2 T 36 pb of integrated luminosity. The ATLAS search contains three T 2s 3 major selection criteria from each ana successively harder pT cuts, the analysis are given below.3
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P Pro Prob
/ T > 300 GeV, one jet with pT (j1 ) > veryHighPT Selection requires E T events are vetoed if there is a second jet with3 | (j2 )| < 4.5 and w ATLAS2and C / T ) < 0.5. Any further jets with | (jBoth or ⌅(j2 , E 2 )| < 4.5 must ha
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Dark matter production in association a single Bothwith ATLAS an In all casesFigure events1:are vetoed if they contain any hard leptons, defined fo since they would and pT (e) > 20 GeV and for muons as | (µ)| < 2.4 and pT (µ) > 10 GeV T The Tcuts used by CMS are similar to those of the LowPT ATLAS 3.1. Comparing Various Mono-Jet An / T > 150 GeV and one jet with pT (j1 ) > 110 ‐Nucleon are selected by requiring E | (j1 )| <‐Nucleon 2.4. A second jet with TpT (j2 ) > 30 GeV is allowed if the azi T the leading jet is ⌅(j1 , j2 ) < 2.0 radians. Events with more than two 1 T 2 vetoed, as are events containing charged leptons with pT > 10 GeV. Th 1 2 observed events in the various searches T is shown in table I. T
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Both ATLAS and CMS impose additional isolation cuts, which we do not mimic i since they would not have a large impact on our results.
3 Figure 1: Dark matter production in association a single in a impose hadron additional collider. isolation cuts, which we do n Bothwith ATLAS andjet CMS David Berge ‐ CERN since they1would not have a large impact on our results.
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Comparing Various Mono-Jet Analyses T
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David B
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Dark matter pair production through a diagram like figure 1 is one of the leading channels for dark matter searches at hadron colliders [3, 4]. The signal would manifest itself as an excess T / T ) events over the Standard of jets plus missing energy (j + E Model background, which consists 3 inv ⇤) + j final states. In the latter case the charged lepton is mainly of (Z ⇤⇤) + j and (W / T final states have been lost, as indicated by the superscript “inv”. Experimental studies of j + E T Extra Dimensions. performed by CDF [22], CMS [23] and ATLAS [24, 25], mostly in the context of
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Felfedezésre ítélve? We are living in a privileged decade
The Decade of the WIMP
Rocky Kolb University of Chicago
MPIK-Heidelberg November 2012
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Értjük-e ezeket a kérdéseket? • Vannak-e eddig fel nem fedezett természeti törvények? • Hogyan érthetjük meg a sötét energia rejtélyét? • Létezik-e több mint három tér-dimenzió? • Egyesülnek-e az alapvető kölcsönhatások? • Miért van oly sokfajta elemi részecske? Van-e esetleg több? • Mi a sötét anyag, elő tudjuk-e állítani laboratóriumban? • Mit mondanak a neutrínók? • Hogyan keletkezett fejlődött a Világegyetem? • Hová tűnt az antianyag?
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