Cosmic radiation in outer and inner space (with some personal - PowerPoint PPT Presentation

Cosmic radiation in outer and inner space (with some personal reminiscences) Péter Király Department of Space Physics and Technology Institute for Particle and Nuclear Physics MTA Wigner RCP ELFT Summer School on Astroparticle Physics Mátraháza, 3. – 7. September 2018.

Main topics What’s in a name? Ionization puzzle -> Höhenstrahlung -> Cosmic rays -> Astroparticles Shifts of emphasis: Ionization, Geo- and HE physics, Space physics, Astrophysics Energy spectra, interactions, composition, directional distributions, origin Terrestrial, atmospheric and magnetospheric effects Sun as a star, heliospheric energetic particles, Voyager and IBEX missions Solar cycle, CR Modulation, Heliosphere, local and farther interstellar, IG medium Early research on cosmic antiparticles, pioneering results of the PAMELA mission Major astroparticle research facilities, and how to proceed P. Király, ELFT Summer School 2018 .

What’s in a name? That which we call a rose By any other word would smell as sweet. (Shakespeare: Romeo and Juliet) Cosmic rays and/or Astroparticles? P. Király, ELFT Summer School 2018 .

IUPAP / C4 Astroparticle physics topics: Some remarks: „Cosmic rays” is obviously a misnomer, created by Millikan in 1925, before the true nature of primaries was revealed, starting in 1929. Long series of conferences, such as ICRC’s (35th in 2017), ECRS’s (26th in 2018), ISVEHCRI (20th in 2018) all have cosmic rays in their name Is „Astroparticle physics” not a misnomer to some extent? Are dark matter, gravity waves and gamma rays really particles? Are secondary CR particles really astroparticles? The name change reflects a shift of emphasis (or of lobbying power?), but conference topics are going to remain, or change only slowly. P. Király, ELFT Summer School 2018 .

Topics of the last International Cosmic Ray Conference I attended P. Király, ELFT Summer School 2018 .

My last European Cosmic Ray Symposia (22nd and 23rd ECRS) in Turku and Moscow, in 2010. and 2012. We hosted the 1988. and 1994. ECRS’s in Balatonfüred. 1994: 2010: Sam Ting was much amused to see it Invited talk in 2012: P. Király, ELFT Summer School 2018 .

From the ionization puzzle to Astrophysics P. Király, ELFT Summer School 2018 .

Why was it so hard to find the source of ionization in shielded containers? Victor Hess in 1912 P. Király, ELFT Summer School 2018 .

From CRs as particles to big accelerators and space physics (1929-1950’s): Emphasis on high-energy physics and geophysics GM-counter, concidence techniques, Bothe and Kolhörster 1929. Rossi, Auger: extended air showers Carl Anderson, 1932: positron, 1936 muon Blackett and Occhialini, 1932: pair creation Further developments in HE physics: discovery of pion by Occhialini and Powell: 1947 Extensive coincidence work by Jánossy and Rochester in Manchester during the war Rochester and Butler, 1947: discovery of the first strange particles (Kaon, Lambda) Important developments in geophysical and heliospheric applications of cosmic rays Latitude effect, longitude effect, modulation, Forbush effect, underground physics Start of radio work in Jodrell Bank, originally for EAS P. Király, ELFT Summer School 2018 .

P. Király, ELFT Summer School 2018 .

After the low luminosity and random directions of cosmic ray secondaries made further HE research difficult, accelerators took over (discoveries of antiprotons and antineutrons). With space age, new perspectives opened for low-energy CR and heliospheric research. In HE physics, CRs still played a role as „poor man’s accelerators”. P. Király, ELFT Summer School 2018 .

Starting from the early sixties, new astronomies (UV, IR, X, Gamma, Nu) were born and came of age, but still kept a close connection to CR physics. Also, magneto- and heliospheric plasma, particles and fields were studied by various missions. One important new field was neutrino physics, where George Marx played a prominent part, starting a new and high-level conference series in Balatonfüred. A picture taken over from a paper by András Patkós. But I am also there, sticking out my head in the back row. P. Király, ELFT Summer School 2018 .

Galactic cosmic ray elemental abundances at GeV energies: evidence for a long time spent in the Galaxy by primordial CRs, interacting with nuclei of the interstellar medium. P. Király, ELFT Summer School 2018 .

The 41-year old Voyager mission, the outer Heliosphere and beyond. (Veterans in heliospheric boundary region) P. Király, ELFT Summer School 2018 .

The region of outward streaming solar wind: the Heliosphere. Veteránok 2017 The supersonic inner region ends in the termination shock, surrounded by the subsonic heliosheath, separated from interstellar plasma by the heliopause. V1 Visszaáramló V2 napszél

2-dimensional models of solar wind – interstellar wind interactions (in Axford’s dinner plate and in my kitchen sink) P. Király, ELFT Summer School 2018 .

Veteránok 2017 The Voyagers and their still functioning instrument groups UV spectrometer Low-energy charged particles Plasma detector High-gain CRs antenna Magnetometer boom Thermoelectric generator Electronics Plasma-wave antenna

How Voyager-2 radial speed changed Veteránok 2017 due to gravitational assist by planets. Smooth path for visiting 4 outer planets (next possibility comes in 176 years!)

P. Király, ELFT Summer School 2018 .

Dead and still functioning heliospheric spacecraft (should send birthday greetings to Voyager-1 today!) Some other important data for the two Voygers: End of planetary mission: 1980 for V1, late 1989 for V2, after passing Neptune. V1 crossed termination shock: 15th December 2004, at 94 AU from the Sun V2 crossed termination shock: 30th September 2007, at 84 AU from the Sun V1 crossed the heliopause into interstellar space: 25 September 2012 at 121 AU Power of radio transmitter: 22 W My personal involvement: member of senior review team in Washington, 1995 P. Király, ELFT Summer School 2018 .

Some important Voyager results in the extended mission, beyond the planets P. Király, ELFT Summer School 2018 .

Veteránok 2017 MeV ion count rates of V1 and V2 before and after the termination shock transits (TS1, TS2), and vanishing counts for V1 beyond the heliopause (HP1).

How solar wind velocity components and thermal speed changed at V2 transiting the termination shock

>70 Mev, mainly cosmic ray intensity variations as seen by V1 and V2 at the same time, but at different solar distances. No big changes are seen at crossing the Termination shock. Forbush effect seen in 2006. Just before and after the heliopause count rates are not correlated.

Solar activity as measured by sunspot numbers, and cosmic ray intensity as measured by a high-latitude neutron monitor (Thule in Greenland).

Veteránok 2017 2012 Celebration of the centenary of the discovery of cosmic rays, and start of exit of Voyager-1 from the heliosphere

Memorial tablet for Victor Hess in Bad Saarow-Pleskov, 7 August 2002 P. Király, ELFT Summer School 2018 .

Some of the distinguished guests of the centenary celebration P. Király, ELFT Summer School 2018 .

Remarkable coincidences: Heliospheric MeV ion countrates sharply decreased just before the centenary of CR discovery, indicating an imminent exit of V1 from the Heliosphere at 121.5 Au solar distance. Although countrates recovered soon, then dropped and recovered again, and on the 25th August practically vanished. Incidentally, Neil Armstrong died on the same day. Official confirmation of the exit came only more than 1 year later.

Veteránok 2017 Behaviour of heliospheric MeV and mostly cosmic ray > 70 MeV ions before V1 exited the Heliosphere. Explanation: the heliopause moved faster than V1, due to changes in the dynamical pressure of the solar wind. The cosmic ray count rate has not changed much in the subsequent 6 years.

Might something similar be happening to Voyager-2 right now? P. Király, ELFT Summer School 2018 .

Veteránok 2017 Energy spectra of protons and alpha particles inside and outside of the heliosphere: V2 was still inside (blue, power spectrum at low energies), while V2 outside (red).

V-2 plasma data throughout the mission Radial streaming velocity Plasma density x R^2 Log of plasma temperature

Several ambitious big projects have brought first results and are promising much more in the field of astroparticle physics. But one should not forget: microscopes might contribute to science as much as giant telescopes. Solar- heliospheric research continues to be very useful for understanding processes on larger and more energetic scales. The magnetosphere of Earth Jim Cronin and Alan Watson, fathers of PAO P. Király, ELFT Summer School 2018 .

Thanks for your attention!

P. Király, ELFT Summer School 2018 .

Veteránok 2017 (CME: Coronal Mass Ejection, vagyis anyagkidobódás a napkoronából)

Tavaly decemberben érkezett hír: A Voyager-1 szonda élettartamát sikerült pár évvel meghosszabbítani a 37 éve be sem kapcsolt fúvókák újraindításával