Baryogenesis and Leptogenesis Bhupal Dev Washington University in St. Louis 16th Conference on Flavor Physics & CP Violation (FPCP 2018) UoH and IITH, Hyderabad, India July 17, 2018 Matter-Antimatter Asymmetry24. Big-Bang nucleosynthesis 3 8 J. M. Cline 8000 15% higher η value accepted η value 15% lower η value 6000 WMAP data 4000 2000 CMB temperature fluctuations 0 10 100 1000 multipole, l Fig. 2. Dependence of the CMB Doppler peaks on η. [J. Cline ’06] as large as the presently observable universe. There seems tobenoplausibleway of separating baryons and antibaryons from each other on suchlargescales. It is interesting to note that in a homogeneous, baryon-symmetric universe, there would still be a few baryons and antibaryons left since annihilations aren’t perfectly efficient. But the freeze-out abundance is nB nB¯ 20 = 10− (1.7) nγ nγ ≈ (see ref. [4], p. 159), which is far too small for the BBN or CMB. Figure 24.1: The primordial abundances of 4He,[Particle D, 3He, Data and 7 GroupLi as predicted ’17] In the early days of big bang cosmology, the baryon asymmetry was consid- by the standard model of Big-Bang nucleosynthesis — the bandsshowthe95%ered to be an initial condition, but in the context of inflationthisideaisnolonger CL range [5]. Boxes indicate the observed light element abundances. The narrowtenable. Any baryon asymmetry existing before inflation would be diluted to a vertical band indicatesn theB − CMBn measureB¯ of the cosmic baryon−10density, while thenegligible value during inflation, due to the production of entropy during reheat- wider bandη indicatesB ≡ the BBN D+4He concordance' 6.1 range× 10 (both at 95% CL). ing. One number =⇒ BSM Physics nγ It is impressive that A. Sakharov realized the need for dynamically creating 2 predictions and thus in the key reaction cross sections. For example, it has been suggestedthe baryon asymmetry in 1967 [5], more than a decade before inflation was in- 3 [31,32] that d(p, γ) He measurements may suffer from systematic errors and be inferiorvented. to The idea was not initially taken seriously; in fact itwasnotreferenced again, with respect to the idea of baryogenesis, until 1979 [6]. Now it has 1040 December 1, 2017 09:35 citations (encouragement to those of us who are still waitingforourmostinterest- ing papers to be noticed!). It was only with the advent of grandunifiedtheories, Baryogenesis Ingredients [Sakharov ’67] Necessary but not sufficient.Ingredients are not enough. + = 6 The Standard Model hasA allmechanism the basic for baryogenesis ingredients, is needed. but No known mechanism works in the Standard Model. CKM CP violation is too small (by ∼ 10 orders of magnitude). Observed Higgs boson mass is too large for a strong first-order phase transition. Requires New Physics! New sources of CP violation. A departure from equilibrium (in addition to EWPT) or modify the EWPT itself. Baryogenesis Dynamical generation of baryon asymmetry. Basic ingredients: [Sakharov (JETP Lett. ’67)] B violation, C & CP violation, departure from thermal equilibrium 3 Baryogenesis Ingredients [Sakharov ’67] Ingredients are not enough. + = 6 The Standard Model hasA allmechanism the basic for baryogenesis ingredients, is needed. but No known mechanism works in the Standard Model. CKM CP violation is too small (by ∼ 10 orders of magnitude). Observed Higgs boson mass is too large for a strong first-order phase transition. Requires New Physics! New sources of CP violation. A departure from equilibrium (in addition to EWPT) or modify the EWPT itself. Baryogenesis Dynamical generation of baryon asymmetry. Basic ingredients: [Sakharov (JETP Lett. ’67)] B violation, C & CP violation, departure from thermal equilibrium Necessary but not sufficient. 3 Baryogenesis Ingredients [Sakharov ’67] Ingredients are not enough. + = 6 A mechanism for baryogenesis is needed. No known mechanism works in the Standard Model. New sources of CP violation. A departure from equilibrium (in addition to EWPT) or modify the EWPT itself. Baryogenesis Dynamical generation of baryon asymmetry. Basic ingredients: [Sakharov (JETP Lett. ’67)] B violation, C & CP violation, departure from thermal equilibrium Necessary but not sufficient. The Standard Model has all the basic ingredients, but CKM CP violation is too small (by ∼ 10 orders of magnitude). Observed Higgs boson mass is too large for a strong first-order phase transition. Requires New Physics! 3 Baryogenesis Ingredients [Sakharov ’67] Ingredients are not enough. + = 6 A mechanism for baryogenesis is needed. No known mechanism works in the Standard Model. Baryogenesis Dynamical generation of baryon asymmetry. Basic ingredients: [Sakharov (JETP Lett. ’67)] B violation, C & CP violation, departure from thermal equilibrium Necessary but not sufficient. The Standard Model has all the basic ingredients, but CKM CP violation is too small (by ∼ 10 orders of magnitude). Observed Higgs boson mass is too large for a strong first-order phase transition. Requires New Physics! New sources of CP violation. A departure from equilibrium (in addition to EWPT) or modify the EWPT itself. 3 Leptogenesis [Fukugita, Yanagida ’86; Akhmedov, Rubakov, Smirnov ’98; Pilaftsis, Underwood ’03; Ma, Sahu, Sarkar ’06; Deppisch, Pilaftsis ’10; Fong, Gonzalez-Garcia, Nardi, Peinado ’13; BD, Millington, Pilaftsis, Teresi ’14; Aristizabal Sierra, Tortola, Valle, Vicente ’14; ...] Cogenesis [Kaplan ’92; Farrar, Zaharijas ’06; Sahu, Sarkar ’07; Kitano, Murayama, Ratz ’08; Kaplan, Luty, Zurek ’09; Berezhiani ’16; Bernal, Fong, Fonseca ’16; Narendra, Patra, Sahu, Shil ’18; ...] WIMPy baryogenesis [Cui, Randall, Shuve ’11; Cui, Sundrum ’12; Racker, Rius ’14; Dasgupta, Hati, Patra, Sarkar ’16; ...] Can also go below the EW scale, independent of sphalerons, e.g. Post-sphaleron baryogenesis [Babu, Mohapatra, Nasri ’07; Babu, BD, Mohapatra ’08] Dexiogenesis [BD, Mohapatra ’15; Davoudiasl, Zhang ’15] Testable effects: collider signatures, gravitational waves, electric dipole moment, 0νββ, lepton flavor violation, n − n¯ oscillation, ... This talk: Low-scale leptogenesis Testable Baryogenesis Many ideas, some of which can be realized down to the (sub)TeV scale, e.g. EW baryogenesis [Kuzmin, Rubakov, Shaposhnikov ’87; Cohen, Kaplan, Nelson ’90; Carena, Quiros, Wagner ’96; Cirigliano, Lee, Tulin ’11; Morrissey, Ramsey-Musolf ’12; ...] 4 Cogenesis [Kaplan ’92; Farrar, Zaharijas ’06; Sahu, Sarkar ’07; Kitano, Murayama, Ratz ’08; Kaplan, Luty, Zurek ’09; Berezhiani ’16; Bernal, Fong, Fonseca ’16; Narendra, Patra, Sahu, Shil ’18; ...] WIMPy baryogenesis [Cui, Randall, Shuve ’11; Cui, Sundrum ’12; Racker, Rius ’14; Dasgupta, Hati, Patra, Sarkar ’16; ...] Can also go below the EW scale, independent of sphalerons, e.g. Post-sphaleron baryogenesis [Babu, Mohapatra, Nasri ’07; Babu, BD, Mohapatra ’08] Dexiogenesis [BD, Mohapatra ’15; Davoudiasl, Zhang ’15] Testable effects: collider signatures, gravitational waves, electric dipole moment, 0νββ, lepton flavor violation, n − n¯ oscillation, ... This talk: Low-scale leptogenesis Testable Baryogenesis Many ideas, some of which can be realized down to the (sub)TeV scale, e.g. EW baryogenesis [Kuzmin, Rubakov, Shaposhnikov ’87; Cohen, Kaplan, Nelson ’90; Carena, Quiros, Wagner ’96; Cirigliano, Lee, Tulin ’11; Morrissey, Ramsey-Musolf ’12; ...] Leptogenesis [Fukugita, Yanagida ’86; Akhmedov, Rubakov, Smirnov ’98; Pilaftsis, Underwood ’03; Ma, Sahu, Sarkar ’06; Deppisch, Pilaftsis ’10; Fong, Gonzalez-Garcia, Nardi, Peinado ’13; BD, Millington, Pilaftsis, Teresi ’14; Aristizabal Sierra, Tortola, Valle, Vicente ’14; ...] 4 Can also go below the EW scale, independent of sphalerons, e.g. Post-sphaleron baryogenesis [Babu, Mohapatra, Nasri ’07; Babu, BD, Mohapatra ’08] Dexiogenesis [BD, Mohapatra ’15; Davoudiasl, Zhang ’15] Testable effects: collider signatures, gravitational waves, electric dipole moment, 0νββ, lepton flavor violation, n − n¯ oscillation, ... This talk: Low-scale leptogenesis Testable Baryogenesis Many ideas, some of which can be realized down to the (sub)TeV scale, e.g. EW baryogenesis [Kuzmin, Rubakov, Shaposhnikov ’87; Cohen, Kaplan, Nelson ’90; Carena, Quiros, Wagner ’96; Cirigliano, Lee, Tulin ’11; Morrissey, Ramsey-Musolf ’12; ...] Leptogenesis [Fukugita, Yanagida ’86; Akhmedov, Rubakov, Smirnov ’98; Pilaftsis, Underwood ’03; Ma, Sahu, Sarkar ’06; Deppisch, Pilaftsis ’10; Fong, Gonzalez-Garcia, Nardi, Peinado ’13; BD, Millington, Pilaftsis, Teresi ’14; Aristizabal Sierra, Tortola, Valle, Vicente ’14; ...] Cogenesis [Kaplan ’92; Farrar, Zaharijas ’06; Sahu, Sarkar ’07; Kitano, Murayama, Ratz ’08; Kaplan, Luty, Zurek ’09; Berezhiani ’16; Bernal, Fong, Fonseca ’16; Narendra, Patra, Sahu, Shil ’18; ...] WIMPy baryogenesis [Cui, Randall, Shuve ’11; Cui, Sundrum ’12; Racker, Rius ’14; Dasgupta, Hati, Patra, Sarkar ’16; ...] 4 Testable effects: collider signatures, gravitational waves, electric dipole moment, 0νββ, lepton flavor violation, n − n¯ oscillation, ... This talk: Low-scale leptogenesis Testable Baryogenesis Many ideas, some of which can be realized down to the (sub)TeV scale, e.g. EW baryogenesis [Kuzmin, Rubakov, Shaposhnikov ’87; Cohen, Kaplan, Nelson ’90; Carena, Quiros, Wagner ’96; Cirigliano, Lee, Tulin ’11; Morrissey, Ramsey-Musolf ’12; ...] Leptogenesis [Fukugita, Yanagida ’86; Akhmedov, Rubakov, Smirnov ’98; Pilaftsis, Underwood ’03; Ma, Sahu, Sarkar ’06; Deppisch, Pilaftsis ’10; Fong, Gonzalez-Garcia, Nardi, Peinado ’13; BD, Millington, Pilaftsis, Teresi ’14; Aristizabal Sierra, Tortola, Valle, Vicente ’14; ...] Cogenesis [Kaplan ’92; Farrar, Zaharijas ’06; Sahu,