groping for the (cosmic ray) knee frank jones, robert streitmatter and demos kazanas physics at the...
TRANSCRIPT
![Page 1: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/1.jpg)
Groping for the (Cosmic Ray) Knee
Frank Jones, Robert Streitmatter and Demos Kazanas
Physics at the End of the Galactic Cosmic Ray SpectrumAspen, April 25 – May 1, 2005
![Page 2: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/2.jpg)
If Simon Swordy didn’t
exist we would have to invent him.
![Page 3: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/3.jpg)
Two Component CR Spectrum
Log E (eV)
10 11 12 13 14 15 16 17 18 19 20 21
Flu
x X
E2.
7
-1
0
1
2nd Tooth Fairy
1st Tooth Fairy
![Page 4: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/4.jpg)
<ln(A)>
Energy (GeV)
104 105 106 107 108
<ln
(A)>
0
1
2
3
4
CASA - BLANCA
JACEE
Baloon Data
RUNJOB
JACEE2
SPASE
KASCADE e*
KASCADE hadron
KASCADE nn
HiRes
HEGRA crt
HEGRA airobic
Havera Park
Fly's Eye
DICE
Chacaltaya
CASA - MIA
BLANCA
KASCADE max
![Page 5: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/5.jpg)
<ln(A)>
Energy (GeV)
104 105 106 107 108
<ln
(A)>
0
1
2
3
4
CASA - BLANCAFly's EyeDICEBLANCAKASCADE max
![Page 6: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/6.jpg)
One Knee Scenario:
There is another proton component that would
explain the drop in <lnA> just below the knee.
![Page 7: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/7.jpg)
Energy (GeV)
102 103 104 105 106 107 108
Flu
x X
E2.
5 (
m2
s sr
/Gev
1.5 )
-1
102
103
104
105
HePother
Ptotal
All Particle
Fe
CNONe-S
PSN
![Page 8: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/8.jpg)
<ln(A)>
Energy (GeV)
104 105 106 107 108
<ln
(A)>
0
1
2
3
4
Theory: Toy ModelCASA - BLANCAFly's EyeDICEKASCADE maxKASCADE max
![Page 9: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/9.jpg)
•Vernov, Zatsepin, Khristiansen, and Chudakov, Report to the All Union Conference on Cosmic Rays, Tbilisi, 1956
•Kulikov and Khristiansen, JETP 35, 635, 1958
Why was the knee discovered? – New Physics?
![Page 10: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/10.jpg)
The Idea!
•A new production channel opens up in the particle collision cross section.
•Some products are “invisible” resulting in “lost” energy.
•Produces apparent steepening of the cosmic-ray spectrum.
•We follow the approach of Kazanas and Nicolaidas
![Page 11: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/11.jpg)
Toy Model
![Page 12: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/12.jpg)
![Page 13: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/13.jpg)
![Page 14: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/14.jpg)
![Page 15: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/15.jpg)
![Page 16: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/16.jpg)
![Page 17: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/17.jpg)
![Page 18: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/18.jpg)
To obtain the bend in the observed spectrum it turns out that we require:
![Page 19: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/19.jpg)
Toy Model: Spectrum at Knee
Energy (GeV)
105 106 107 108
Dif
fere
nti
al F
lux
X E
2.8
(Arb
itra
ry U
nit
s)
10
100
![Page 20: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/20.jpg)
<ln(A)>
Energy (GeV)
104 105 106 107 108
<ln
(A)>
0
1
2
3
4
![Page 21: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/21.jpg)
To make the mass appear to become heavier we need to make the hadronic cross sections increase at the same energy that the new channel opens up.
Typically, the mass of a primary particle is determined by the depth in the atmosphere of the shower maximum.
What could make the mass look heavier?
![Page 22: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/22.jpg)
Toy Model: Shower Maximum
• In an air shower that involves the new process there are two effects that can raise the position of the shower maximum.– If the cross section increases for energies > Ec
then each leg of the cascade in this energy region will be shorter.
– If the multiplicity increases there is an additional raising of the maximum because the energy is diluted quicker.
![Page 23: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/23.jpg)
![Page 24: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/24.jpg)
![Page 25: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/25.jpg)
![Page 26: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/26.jpg)
![Page 27: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/27.jpg)
![Page 28: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/28.jpg)
<ln(A)>
Energy (GeV)
104 105 106 107 108
<ln
(A)>
0
1
2
3
4
![Page 29: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/29.jpg)
Shower ElongationToy Model
log(Energy) (eV)10 11 12 13 14 15 16 17 18 19 20
Xm
ax (
g/cm
2 )
200
400
600
800
1000
![Page 30: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/30.jpg)
Shower ElongationToy Model
log(Energy) (eV)10 11 12 13 14 15 16 17 18 19 20
Xm
ax (
g/cm
2 )
200
400
600
800
1000
![Page 31: Groping for the (Cosmic Ray) Knee Frank Jones, Robert Streitmatter and Demos Kazanas Physics at the End of the Galactic Cosmic Ray Spectrum Aspen, April](https://reader035.vdocuments.mx/reader035/viewer/2022070411/56649f4d5503460f94c6da2e/html5/thumbnails/31.jpg)