Capdevielle, J N

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29th International Cosmic Ray Conference Pune (2005) 6, 117120Remarkable events and EAS properties in the knee energy region up tothe LHC energy rangeJ.N. Capdevielle , R. Attallahand M. Talai(a) APC, College de France,11 place M. Berthelot, 75231 Paris Cedex 05 , France(b) Department of Physics, University Badji Mokhtar, Annaba, AlgriePresenter: J.N. Capdevielle (capdev@cdf.in2p3.fr), fra-capdevielle-JN-abs1-he12-posterAfter extensive simulations of  ray families with CORSIKA in the energy region 3  10  -10  eV, we haveobtained from the fluctuations generated by standard 	 collider physics alignments of secondaries in thestratosphere and at ground level. The remarkable event registrated on the Concorde doesn’t fit well howeverthose cases of artificial coplanar emission ; The possible hints of new mechanisms, especially the valencediquark breaking, are considered in the perspective of associated consequences visible in the EAS development.1. IntroductionOne event exhibiting aligned secondaries presented in the analysis of the earliest emulsion chamber experi-ment of Chacaltaya  and the the double core structure observed in binocular families up to a total energyof 1500 TeV could be the preliminary form of coplanar emission   . After those possible precursors, theattention was motivated by the events recorded in Pamir X ray chamber   , in Kambala, in Kascade, but alsoin balloon experiments (RUNJOB) and in the low stratosphere with high resolution X ray emulsion chambersin the Concorde   ; in this last situation,the geometrical criteria used to select an alignment treat directly thecoordinates of the individual  ’s, either the linear coefficient   :ﬀ ﬁﬃﬂ! #"$&%"(' *)+$,%)-'.ﬁﬃﬂ *"$/%"!'10.ﬁ&ﬂ *)!$/%)2'0(1)or the parameter 3ﬂintroduced by Pamir Collaboration   and defined as:3ﬂﬁﬂ54687469;:=<?>A@97	 	$' 	$'(2)where @97 is the angle between the straight lines joining the B5C#D and EAC#D particles to the FGCHD one ( IKJL@97JNM ).Both approaches help to select straight structures when their absolute values are close to 1 and have comparableadvantages for this specific planarity   In our simulation, the primary particle is assumed to be in turn aproton, an O -particle ( P0He), a carbon ( 0Q C) nucleus, a magnesium (0P0Mg) nucleus and in the end an iron ( Q0Q Fe)nucleus. The zenith angle is chosen at random in the range I – AI2R . The asymmetry parameter 3ﬂis calculatedfor the 4 and 5 most energetic secondary hadronic clusters. Alignments have been easily obtained (Figure 1),independently on the models (as far as they have similar transverse momenta distribution),and practically onthe primary mass and on the primary energy  S . As shown on the Figure 2, for the Pamir experiment, the threemodels involved give values very close to each other and, within the error bars, independent of the primaryparticle type. They are equal on average to ( UT WVXAT  )% for the aligned events with 3PﬀYI2T Z and ( ?T WV[I2T  )%for 3\YIUT Z .From our set of simulations, we show as an other example the dependence on the primary energy at balloonaltitude (Figure 3).118 J.N. Capdevielle, R. Attallah and M. Talai-20020406080100120-50 0 50 100a)x (mm)y (mm)-100-80-60-40-20020-25 0 25 50 75b)x (mm)y (mm)2468101 10 102Fraction (%) of aligned eventsa)01231 10 102Primary particle mass number (A)b)Figure 1. Left: Examples of a pair of simulated events similar to JF2af2 with 23 (a) and 18 (b) aligned ] -rays ( ] +e ^ )above 10 TeV Right: Calculated fractions (%) of the aligned events with _2`badcAe f (a) and _hgiadce f (b)for the Pamirexperimental condition obtained by different hadronic interaction models: HDPM (opentriangle), QGSJET (fullsquare)and SYBILL (opensquare). The dashed line represents in both cases the average value.2. The Concorde event near j-kmln eVTracing back the events produced with CORSIKA (Figure 1), we have observed that an unbalanced o+p receivedin the first collision on an energetic Mq could produce an alignment when the cascade starts 10km above thechamber.DPMJET HDPM QGSJET SIBYLL VENUSrrYI2T s 0.7 1.5 0.6 0.5 0.93PﬀYI2T Z 7.4 8.0 7.4 7.4 7.1Table 1. Calculated fractions (%) of the aligned events with at least 4 ] -rays ( ] +e ^ ) above 10 TeV for with t uGt8avcAe wyx(rst row) and _-`za{ce f (second row) for different high energy hadronic interaction models.The primary cosmic ray particle in Table 1 is assumed to be a proton of 10  GeV, the observation level isidentical to the Concorde flight altitude (17 km) and the zenith angle is selected at random in the range 0–70 R . The number of simulated showers in each case is equal to 10 P ; the results from the different hadronicmodels are on the whole consistent with one another. Among the 211  ’s of the JF2aF2 Concorde event, weRemarkable events in the knee energy region ... 1190246810121410151016101710181019Fraction (%) of aligned events a)024681012141016101710181019Primary energy (eV)b)Figure 2. Calculated fractions (%) of the aligned events with _2`za|ce f for a primary proton (a) and a primary iron nucleus(b) as a function of the primary energy obtained by different hadronic interaction models: DPMJET (opencircle), HDPM(opentriangle), QGSJET (fullsquare), SYBILL (opensquare) and VENUS (opendiamond). The dashed line represents inboth cases the average value.show on a lego plot the energy deposited in a plane perpendicular to the axis by 34  ’s (about one half ofthe total energy deposited, i.e. yS?IAI TeV). Inside , the alignment, the four most energetic  ’s with respectiveenergies, 300 TeV, 105 TeV, 75 TeV and 53 TeV are lying on a perfect straight line   with } I2T sAs?sA Theinvariant mass histograms for the different clusters (Fig.5) suggest an interaction level at about 100m above theConcorde, in contradiction with the simulation on the basis of standard physics requiring about 10km. We haveverified on a small sample of simulated events that, in spite of a few secondaries of 2nd or 3rd generation (viabremsstrahlung or pair production) that those histograms, from the position of their maximum, return correctlythe the origin of the collisions (at least in the stratosphere). Taking the 3 most important clusters ( ZG~? ofthe energy , ~I- of the number of  ’s) as well as the whole event   , we obtain a distance of the vertex tothe chamber of ZAI$yI?I , instead of a distance in the range of I km. Such circumstance suggests a violentphenomena separating the valence quarks of the proton projectile, especially the valence diquark, which cannotbe recombined with a quark of the sea, suppressing the leading baryon at the end of the collision.One hypothesis is that the original rotating relativistic string between the valence quark and the valence diquarkbecomes a more complex system with a secondary string (centered on the barycenter of the diquark) betweenthe two quarks partners of the diquark. The maximal tension of the strings occurs when the quarks are at thelargest distance from each other, i.e. when the 3 partons are on a common diameter which would be the axisof the fragmentation. The shorter mean free path of the diquark in the target nuclei could help the phenomena.As a consequence of the suppression of the leading particle, T  is expected to level off during one decadeafter the maximum  ~ and some typical behavior would have to be observed in EAS (changes of slope inmuon electron dependence, flattening in the age parameter versus size, different absorption length,enhancedsteepness of the most energetic  ’s and hadrons spectra). From other part, there have been few simulations withprimary nuclei, and the recent proposition of a predominant O component suggests to examine more carefullythe asymmetries in light nuclei collision which explain the coplanar emission, for instance effects like thegiant dipole resonance observed at very low energy, separating on each side of the nucleus the protons and theneutrons.120 J.N. Capdevielle, R. Attallah and M. TalaiFigure 3. Left: Lego plot of the energy deposited by 34 ] ’s in the alignment (energy in TeV on vertical axis, x, y in mm)Right: An example of the histogram of invariant mass for cluster A, with the mass of the ( , the maximum gives aninteraction distance near 100m3. ConclusionsA large proportion of the alignments may be explained by fluctuations. However, the alignments observed inthe stratosphere indicate the necessity of a more careful analysis and the collection of new events, in the lowstratosphere. I?IAI Hours could be available for a scientific payload during the certification of the Airbus A380.The flights carried at an altitude of yUT km ( ~I$[Ł{0) with 10 emulsion chambers , similar to those usedin Concorde, would multiply by 100 the statistics of remarkable  ray families. This remains the most simpleapproach to the behavior of the valence quarks,at energies close of the LHC energy range.References[1] J. Nishimura for the Japan-Brasilian collab. Akashi M. 1965 Proc. 9th ICCR (London) vol 2, p 745[2] Lattes C.M. G. , Phys. Rep. (1980), 65, 3[3] Borisov A S 1984 Proc. 3rd Int. Symp. on Very High Energy Cosmic Ray Interactions (Tokyo) 49[4] Capdevielle J.N., J. Phys. G,(1988) 14, 503[5] Capdevielle J. N., Nucl.Phys.B (2001), 97, 126[6] Attallah R., Capdevielle J. N. , Talai M. , J.Phys. G, 31 (2005)373-388 and ref herein[7] Capdevielle J.N. et al.,Proc. 28th ICRC, Tsukuba (2003), p.1599

Remarkable events and EAS properties in the knee energy region up to the LHC energy range

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